MLA-C01 AWS Certified Machine Learning Engineer - Associate Questions and Answers

SageMaker Clarify is designed to provide explainability for ML models. It can analyze feature importance and explain how input features influence the model's predictions. By using Clarify with the deployed SageMaker model, the ML engineer can generate insights and present them to stakeholders to explain the sentiment analysis predictions effectively.

By creating IAM policies with specific permissions, you can restrict access to Amazon S3 buckets or objects based on the user's business group. These policies can be attached to IAM users or IAM roles associated with the ML engineers, ensuring that each engineer can only access training data belonging to their group. This approach is secure, scalable, and aligns with AWS best practices for access control.

Adding resource tagging to the SageMaker user profile enables tracking and monitoring of costs associated with specific SageMaker resources.

AWS Budgets allows setting thresholds and automated alerts for costs and usage, making it the ideal service to notify the ML engineer when compute costs reach a specified limit.

This solution is efficient and integrates seamlessly with SageMaker and AWS cost management tools.

AWS Glue Data Quality provides managed, declarative data quality checks with minimal configuration. Combined with Glue crawlers, it enables automatic schema discovery and quality validation without custom code.

Option A uses native AWS services designed for this exact purpose, minimizing operational overhead. Options B and C require custom code and maintenance. Option D is not designed for data validation.

AWS documentation explicitly recommends Glue Data Quality rules for scalable, automated data quality checks in analytics pipelines.

Therefore, Option A is the correct and AWS-aligned solution.

Partitioning the time-series data by date prefix in the S3 bucket significantly improves query performance in Amazon Athena by reducing the amount of data that needs to be scanned during queries. This allows the ML engineers to efficiently analyze trends over specific time periods, such as the past 3 days. Applying S3 Lifecycle policies to archive partitions older than 30 days to S3 Glacier Flexible Retrieval ensures cost-effective data retention and storage management while maintaining high performance for recent data retrieval.

SageMaker Data Wrangler provides a no-code/low-code interface for preparing and transforming data, including dropping unnecessary columns. By creating a data flow and configuring a transform step, the ML engineer can easily remove correlated or unneeded columns from the Parquet file with minimal effort. This approach avoids the need for custom coding or managing additional infrastructure.

The large gap between training accuracy (99%) and validation accuracy (82%) is a textbook case of overfitting. The model has learned patterns that fit the training data extremely well but do not generalize to unseen data.

AWS ML best practices recommend regularization techniques to address overfitting. Dropout layers randomly deactivate neurons during training, preventing the network from relying too heavily on specific paths. L1 and L2 regularization penalize large weights, reducing model complexity and improving generalization. k-fold cross-validation provides a more robust evaluation by training and validating the model across multiple data splits.

Option A increases complexity, which would worsen overfitting. Option C mixes valid ideas (dimensionality reduction) with unrelated changes (loss function choice) and is less targeted. Option D focuses on data quality but does not directly address model variance.

Therefore, implementing dropout, regularization, and k-fold cross-validation is the correct solution.

Logistic regression is a suitable modeling approach for this requirement because it is designed for binary classification problems, such as predicting whether a customer will require long-term support ("yes" or "no"). It calculates the probability of a particular class and is widely used for tasks like this where the outcome is categorical.

AWS Glue DataBrew supports datasets sourced directly from Amazon S3 paths. To clean and normalize data, AWS documentation specifies using DataBrew recipes, which define transformation steps such as standardization, deduplication, and formatting.

A profile job is used only for data analysis and statistics generation, not for transformation. A recipe job applies actual transformations to the data and writes the output to Amazon S3.

JDBC connections are used for relational databases, not S3 buckets. Therefore, options C and D are invalid.

AWS clearly documents that the correct workflow is:

Create a DataBrew dataset from an S3 path

Define transformations using a recipe

Run a recipe job to produce cleaned data

Thus, Option B is the correct and AWS-aligned answer.

This scenario clearly describes an overfitting problem. The neural network performs well on training data but fails to generalize to evaluation data. According to AWS Machine Learning and deep learning best practices, overfitting occurs when a model learns noise or overly specific patterns in the training data instead of generalizable relationships.

L1 and L2 regularization are well-established techniques to combat overfitting. They work by penalizing large weight values during optimization, effectively constraining the model’s complexity. L1 regularization encourages sparsity, while L2 regularization (weight decay) smooths the weight distribution. AWS documentation recommends regularization as a primary method for improving generalization when a model shows a large gap between training and evaluation performance.

Option B is incorrect because removing dropout layers would increase overfitting, not reduce it. Dropout is itself a regularization technique.

Option C would likely worsen overfitting, as training for more epochs allows the model to memorize the training data even further.

Option D increases model complexity, which again exacerbates overfitting rather than resolving it.

Therefore, penalizing large weights using L1 or L2 regularization is the correct solution.

For real-time video content moderation with minimal operational overhead, AWS documentation recommends using fully managed, purpose-built AI services. Amazon Rekognition provides real-time video analysis capabilities, including content moderation, unsafe content detection, and label recognition for live video streams.

By integrating Rekognition with AWS Lambda, the company can automatically process video frames, extract moderation metadata, and take immediate action (such as flagging or stopping a stream) without managing servers, models, or infrastructure. This serverless architecture scales automatically and minimizes operational complexity.

Option B introduces unnecessary complexity. While Amazon Bedrock LLMs are powerful, they are not required for image-based moderation tasks that Rekognition already handles natively.

Option C is incorrect because using Amazon SageMaker would require model training, endpoint management, and scaling, significantly increasing operational overhead.

Option D is incorrect because Amazon Transcribe and Amazon Comprehend are designed for audio and text analysis, not image or video frame moderation.

Therefore, Amazon Rekognition with AWS Lambda is the most efficient, scalable, and low-maintenance solution for real-time video moderation during live streaming events.

Amazon SageMaker Data Wrangler is a comprehensive tool that streamlines the process of data preparation and offers built-in capabilities for anomaly detection and visualization.

Key Features of SageMaker Data Wrangler:

Data Importation: Connects seamlessly to various data sources, including Amazon S3 and on-premises databases, facilitating the aggregation of transaction logs, customer profiles, and MySQL tables.

Anomaly Detection: Provides built-in analyses to detect anomalies in time series data, enabling the identification of outliers that may indicate fraudulent activities.

Visualization: Offers a suite of visualization tools, such as histograms and scatter plots, to help understand data distributions and relationships, which are crucial for feature engineering and model development.

Implementation Steps:

Data Aggregation:

Import data from Amazon S3 and on-premises MySQL databases into SageMaker Data Wrangler.

Utilize Data Wrangler's data flow interface to combine and preprocess datasets, ensuring a unified dataset for analysis.

Anomaly Detection:

Apply the anomaly detection analysis feature to identify outliers in the dataset.

Configure parameters such as the anomaly threshold to fine-tune the detection sensitivity.

Visualization:

Use built-in visualization tools to create charts and graphs that depict data distributions and highlight anomalies.

Interpret these visualizations to gain insights into potential fraud patterns and feature interdependencies.

Advantages of Using SageMaker Data Wrangler:

Integrated Workflow: Combines data preparation, anomaly detection, and visualization within a single interface, streamlining the ML development process.

Operational Efficiency: Reduces the need for multiple tools and complex integrations, thereby minimizing operational overhead.

Scalability: Handles large datasets efficiently, making it suitable for extensive transaction logs and customer profiles.

By leveraging SageMaker Data Wrangler, the ML engineer can effectively detect anomalies and visualize results, facilitating the development of a robust fraud detection model.

Analyze and Visualize - Amazon SageMaker

Transform Data - Amazon SageMaker

Amazon Kendra is an AI-powered search service designed for semantic search use cases. It allows ingestion of documents from an Amazon S3 bucket using the Amazon Kendra S3 connector. Once the documents are ingested, Kendra enables semantic searches with its built-in capabilities, removing the need to manually generate embeddings or manage a vector database. This approach is efficient, requires minimal operational effort, and meets the requirements for a Retrieval Augmented Generation (RAG) application.

Use case 1:

Summarize the text of a research paper

➡️ Sequence-to-Sequence (seq2seq) algorithm

Why:

Seq2seq models are designed for natural language generation tasks such as text summarization, translation, and paraphrasing. AWS documentation explicitly lists text summarization as a primary use case for the SageMaker seq2seq algorithm.

Use case 2:

Scan every pixel of an image to help self-driving cars identify objects in their path

➡️ Semantic segmentation algorithm

Why:

Semantic segmentation performs pixel-level classification, assigning a class label to every pixel in an image. This is exactly what is required for applications such as autonomous driving, road scene understanding, and object boundary detection.

Use case 3:

Identify abnormal data points in a dataset

➡️ Random Cut Forest (RCF) algorithm

Why:

Random Cut Forest is an unsupervised anomaly detection algorithm. AWS SageMaker RCF is purpose-built to identify outliers, unusual patterns, and anomalies in numerical datasets, making it ideal for fraud detection, monitoring, and abnormal data point detection.

City (name): One-hot encoding

Type_year (type of home and year the home was built): Feature splitting

Size of the building (square feet or square meters): Standardized distribution

City (name): One-hot encoding

Why? The "City" is a categorical feature (non-numeric), so one-hot encoding is used to transform it into a numeric format. This encoding creates binary columns for each unique category (e.g., cities like "New York" or "Los Angeles"), which the model can interpret.

Type_year (type of home and year the home was built): Feature splitting

Why? "Type_year" combines two pieces of information into one column, which could confuse the model. Feature splitting separates this column into two distinct features: "Type of home" and "Year built," enabling the model to process each feature independently.

Size of the building (square feet or square meters): Standardized distribution

Why? Size is a continuous numerical variable, and standardization (scaling the feature to have a mean of 0 and a standard deviation of 1) ensures that the model treats it fairly compared to other features, avoiding bias from differences in feature scale.

By applying these feature engineering techniques, the ML engineer can ensure that the input data is correctly formatted and optimized for the model to make accurate predictions.

To pinpoint inefficiencies inside a training script, AWS recommends using Amazon SageMaker Profiler. SageMaker Profiler provides fine-grained visibility into CPU, GPU, memory, I/O usage, and framework-level operations during training.

By adding profiler annotations directly to the training script, the ML engineer can identify bottlenecks such as inefficient data loading, synchronization delays in DDP, or idle GPU time between training steps.

CloudWatch metrics provide high-level utilization trends but cannot identify exact code-level inefficiencies. CloudTrail is an auditing service and is irrelevant to performance profiling. Model Monitor focuses on data and model quality, not training resource utilization.

Therefore, SageMaker Profiler is the correct tool.

This scenario describes a severely imbalanced classification problem. In such cases, accuracy is a misleading metric, because the model can achieve high accuracy by predicting only the majority class.

AWS ML best practices recommend using F1 score (or precision/recall) when evaluating imbalanced datasets. The F1 score balances false positives and false negatives, making it ideal for assessing minority-class performance.

For image data, image augmentation (rotations, flips, crops, color jitter) is the preferred technique to increase minority-class representation. SMOTE is designed for tabular data and is not suitable for image pixel data.

Therefore, the correct solution is to optimize for F1 score and apply image augmentation.

Thus, Option B is the correct and AWS-aligned answer.

Predicting apartment prices is a regression problem, where the target variable is continuous. AWS documentation states that classification metrics such as accuracy, AUC, and F1 score are not appropriate for regression tasks.

Mean Absolute Error (MAE) measures the average absolute difference between predicted values and actual values. MAE is easy to interpret because it is expressed in the same units as the target variable (for example, dollars), making it especially useful for business-facing problems like price prediction.

AWS best practices recommend MAE for evaluating regression models when understanding average prediction error magnitude is important and when robustness to outliers is desired.

Therefore, Option D is the correct and AWS-aligned answer.

AWS documentation identifies Amazon SageMaker Clarify as the primary service for detecting, measuring, and explaining bias in ML models, particularly across demographic and sensitive attributes such as age, gender, and location. Clarify can analyze bias before training, after training, and during inference, making it suitable for audit and compliance requirements.

SageMaker Clarify generates bias reports using established fairness metrics such as difference in positive proportions, disparate impact, and conditional demographic disparity. These reports are exportable and auditor-friendly, directly meeting the requirement to explain bias to an external party.

AWS Glue DataBrew focuses on data preparation and quality, not bias detection. Amazon QuickSight does not provide ML fairness metrics. Amazon CloudWatch captures operational metrics, not demographic bias indicators.

AWS best practices explicitly recommend SageMaker Clarify for model transparency, fairness evaluation, and regulatory reporting.

Therefore, Option A is the correct and AWS-verified solution.

AWS CodeDeploy provides predefined deployment configurations for ECS that support canary and linear traffic shifting. The ECSCanary10Percent15Minutes configuration shifts 10% of traffic initially, waits 15 minutes, and then shifts the remaining traffic.

This matches the exact requirement: a 10% initial shift followed by the remaining 90% within the specified time window.

Lambda deployment configurations are not applicable to ECS. ECSAllAtOnce does not perform gradual traffic shifting.

AWS documentation explicitly defines ECSCanary10Percent15Minutes for controlled, low-risk ECS deployments.

Therefore, Option C is the correct and AWS-verified answer.

 Why Linear Learner?

SageMaker's Linear Learner algorithm is well-suited for binary classification problems such as fraud detection. It handles class imbalance effectively by incorporating built-in options for weight balancing across classes.

Linear Learner can capture patterns in the data while being computationally efficient.

 Key Features of Linear Learner:

Automatically weights minority and majority classes.

Supports both classification and regression tasks.

Handles interdependencies among features effectively through gradient optimization.

 Steps to Implement:

Use the SageMaker Python SDK to set up a training job with the Linear Learner algorithm.

Configure the hyperparameters to enable balanced class weights.

Train the model with the balanced dataset created using SageMaker Data Wrangler.

Problem Description:

The F1 score, which is a balance of precision and recall, has decreased significantly. This indicates the model's predictions are no longer aligned with the real-world data distribution.

Why Concept Drift?

Concept drift occurs when the statistical properties of the target variable or features change over time. For example, customer behaviors or subscription cancellation patterns may have shifted, leading to reduced model accuracy.

Signs of Concept Drift:

Deviation in performance metrics (e.g., F1 score) over time.

Declining prediction accuracy for certain groups or scenarios.

Solution:

Monitor for drift using tools like SageMaker Model Monitor.

Regularly retrain the model with updated data to account for the drift.

Why Not Other Options?:

B: Model complexity is unrelated if the model initially performed well.

C: Data quality issues would have been detected during baseline analysis.

D: Incorrect ground truth labels would have resulted in a consistently poor baseline.

Conclusion: The decrease in F1 score is most likely due to concept drift in the customer data, requiring retraining of the model with new data.

For near real-time predictions, AWS documentation recommends Amazon SageMaker real-time inference endpoints. These endpoints support automatic scaling based on metrics such as ConcurrentInvocationsPerInstance, ensuring low latency and high availability during traffic spikes.

For long-running historical analysis, SageMaker Processing jobs are the appropriate solution. Processing jobs are designed for batch workloads, can run for hours, and integrate cleanly with SageMaker pipelines. Scheduling them with Amazon EventBridge provides a fully managed, scalable, and serverless solution.

AWS Lambda is unsuitable for multi-hour workloads. EC2 Auto Scaling adds unnecessary infrastructure management overhead.

Therefore, Options A and C together meet all requirements and align with AWS best practices.

Amazon SageMaker Automatic Model Tuning extracts objective metrics directly from training logs. For custom containers, AWS requires the ML engineer to define a metric definition that specifies a regular expression to parse the desired metric value from standard output.

The ObjectiveMetricName in the tuning job must match the metric captured by the regex. This is the only supported method for integrating custom metrics with SageMaker AMT.

TrainingInputMode does not define metrics. CloudWatch metrics cannot be used as tuning objectives. AMT cannot read metrics from S3 artifacts.

AWS documentation explicitly states that regex-based metric definitions are required for custom metrics in hyperparameter tuning jobs.

Therefore, Option B is the correct and AWS-verified solution.

The requirement specifies real-time streaming ingestion and column-level transformation before sharing data with a vendor. Amazon Kinesis Data Streams is designed for low-latency, real-time data ingestion and delivery.

To extract only required columns from the stream, AWS recommends using Amazon Managed Service for Apache Flink as a stream consumer. Flink enables real-time transformations such as filtering, projection, and enrichment on streaming data before delivering it downstream.

Option A and D are batch-oriented and not suitable for real-time streaming. Option C is incorrect because S3 bucket policies cannot enforce column-level access controls.

Therefore, Kinesis Data Streams combined with Apache Flink meets all requirements.

Amazon SageMaker Pipelines is designed for creating, automating, and managing end-to-end ML workflows, including complex data preprocessing tasks. It supports handling large datasets and can integrate with custom steps, such as NLP transformations. By combining SageMaker Pipelines with Amazon EventBridge, the entire workflow can be triggered and automated efficiently, meeting the requirements for scalability, automation, and processing complexity.

The requirement is to detect irregularities (anomalies) in patient data using an unlabeled dataset, which clearly defines an unsupervised anomaly detection problem. According to AWS documentation, Amazon SageMaker Random Cut Forest (RCF) is purpose-built for detecting anomalies in high-dimensional, continuous datasets such as healthcare metrics and time-series–like records.

RCF works by constructing multiple random decision trees that partition the data. Observations that are isolated closer to the root of these trees are more likely to be anomalies. AWS explicitly recommends RCF for use cases such as fraud detection, system monitoring, and healthcare anomaly detection.

The num_trees hyperparameter controls the number of trees in the forest. Increasing num_trees improves anomaly detection accuracy and stability by averaging anomaly scores across more trees, which is especially important in sensitive domains like healthcare. AWS documentation notes that larger forests provide better generalization and more reliable anomaly scores.

Option A (XGBoost) is a supervised learning algorithm and requires labeled data, making it unsuitable. Option B (k-means) performs clustering but does not explicitly detect anomalies. Option C (DeepAR) is designed for time-series forecasting, not anomaly detection in unlabeled datasets.

Therefore, using Amazon SageMaker Random Cut Forest with a higher num_trees value is the most appropriate, scalable, and AWS-recommended solution.

For near real-time anomaly detection on streaming IoT data, AWS recommends Amazon Managed Service for Apache Flink. Flink is designed for stateful, low-latency stream processing and is well suited for time-series sensor analytics.

A key requirement is application resilience during deployments. Managed Flink supports system rollback, which automatically reverts to the last stable application version if a new deployment fails. This capability ensures uninterrupted processing even if application bugs are introduced, meeting the company’s reliability requirement.

Manual rollback (Option B) introduces operational risk and delays. Amazon Data Firehose (Options C and D) is a delivery service and does not support complex anomaly detection logic or application version rollback.

Therefore, using Managed Flink with system rollback enabled is the correct solution.

AWS documentation strongly recommends using custom Docker containers when ML workloads require consistent access to custom dependencies across processing jobs, training jobs, and pipelines.

By building a single Docker image that contains all required libraries and hosting it in Amazon ECR, the ML engineer ensures that every SageMaker job uses the same runtime environment. This approach eliminates the need for repetitive installation steps and avoids environment drift.

Manually installing libraries in managed containers is error-prone and not reusable across jobs. Notebook instances are not designed to host production jobs and pipelines. Running code externally breaks the SageMaker workflow and increases operational complexity.

Using a custom container is a one-time setup that provides maximum reuse with minimal ongoing effort, making it the least implementation effort option in the long run.

Therefore, Option B is the correct and AWS-recommended answer.

The company lacks programming expertise, so a no-code/low-code solution is required. Amazon SageMaker Canvas includes Data Wrangler’s visual interface, which enables users to import, transform, and prepare data using a graphical workflow.

Data Wrangler in Canvas supports common preprocessing tasks—such as handling missing values, normalization, outlier detection, and feature engineering—without writing code. It integrates directly with Amazon S3 and is suitable for large tabular datasets.

Options A, C, and D require coding skills (Spark, SQL, or Python), which violates the stated constraint.

Therefore, using the visual interface of SageMaker Data Wrangler in Canvas is the correct solution.

SageMaker real-time inference is designed for low-latency, real-time use cases, such as detecting fraudulent transactions in banking applications. It eliminates the delays associated with SageMaker Asynchronous Inference, improving inference performance.

SageMaker Model Monitor provides tools to monitor deployed models for deviations in data quality, model performance, and other metrics. It can be configured to send notifications when a deviation in model quality is detected, ensuring the system remains reliable.

Amazon SageMaker Automated Model Tuning supports several hyperparameter search strategies. Bayesian optimization is explicitly designed to model the relationship between hyperparameters and objective metrics using regression techniques. Based on results from previous training jobs, Bayesian optimization predicts which hyperparameter combinations are most likely to improve model performance and evaluates those next.

AWS documentation highlights Bayesian optimization as the preferred strategy when the hyperparameter search space is small to medium and when training jobs are expensive. Because the algorithm learns from prior runs, it avoids wasting resources on unpromising configurations and converges efficiently.

Grid search exhaustively evaluates all combinations and becomes inefficient even with moderately sized search spaces. Random search does not use information from prior runs and is less efficient. Hyperband focuses on aggressive early stopping and resource allocation, not regression-based sequential selection.

Therefore, Option C is the correct and AWS-verified solution.

Amazon FSx for NetApp ONTAP allows mounting the file system as a network-attached storage (NAS) volume. Since the FSx for ONTAP file system and SageMaker instance are in the same VPC, you can directly mount the file system to the SageMaker instance. This approach ensures efficient access to the 6 TB of training data without the need to duplicate or transfer the data, meeting the requirements with minimal complexity and operational overhead.

This requirement combines asynchronous inference on large datasets with automated data quality monitoring and alerting. AWS documentation explicitly recommends Amazon SageMaker batch transform for large-scale, asynchronous inference workloads. Batch transform jobs process large datasets stored in Amazon S3 without requiring a persistent endpoint, making them cost-effective and scalable.

For data quality monitoring, Amazon SageMaker Model Monitor is the AWS-native solution. Model Monitor can be scheduled to analyze inference data, compare it against a baseline, and detect data quality issues such as missing values, schema changes, or statistical drift. When violations occur, Model Monitor emits metrics to Amazon CloudWatch, where alarms can trigger alerts.

Options A, B, and C lack ML-aware data quality monitoring capabilities. AWS Glue and Batch are not designed for model data quality analysis, and CloudTrail tracks API activity—not data quality.

AWS best practices clearly position Batch Transform + Model Monitor as the correct architecture for asynchronous inference with automated monitoring and alerting.

Therefore, Option D is the correct and AWS-verified solution.

When running consecutive training jobs in Amazon SageMaker, infrastructure provisioning can introduce latency, as each job typically requires the allocation and setup of compute resources. To minimize this startup time and enhance efficiency, Amazon SageMaker offers Managed Warm Pools.

Key Features of Managed Warm Pools:

Reduced Latency: Reusing existing infrastructure significantly reduces startup time for training jobs.

Configurable Retention Period: Allows retention of resources after training jobs complete, defined by the KeepAlivePeriodInSeconds parameter.

Automatic Matching: Subsequent jobs with matching configurations (e.g., instance type) can reuse retained infrastructure.

Implementation Steps:

Request Warm Pool Quota Increase: Increase the default resource quota for warm pools through AWS Service Quotas.

Configure Training Jobs:

Set KeepAlivePeriodInSeconds for the first training job to retain resources.

Ensure subsequent jobs match the retained pool's configuration to enable reuse.

Monitor Warm Pool Usage: Track warm pool status through the SageMaker console or API to confirm resource reuse.

Considerations:

Billing: Resources in warm pools are billable during the retention period.

Matching Requirements: Jobs must have consistent configurations to use warm pools effectively.

Alternative Options:

Managed Spot Training: Reduces costs by using spare capacity but doesn’t address startup latency.

SageMaker Training Compiler: Optimizes training time but not infrastructure setup.

SageMaker Distributed Data Parallelism Library: Enhances training efficiency but doesn’t reduce setup time.

By using Managed Warm Pools, the company can significantly reduce startup latency for consecutive training jobs, ensuring faster experimentation cycles with minimal operational overhead.

AWS Documentation: Managed Warm Pools

AWS Blog: Reduce ML Model Training Job Startup Time

This problem describes a recommendation system with millions of records, many categorical variables, and a high-dimensional sparse feature space created by one-hot encoding. AWS documentation explicitly recommends Amazon SageMaker Factorization Machines (FM) for such use cases.

Factorization Machines are designed to handle sparse datasets efficiently and to model interactions between categorical features without explicitly enumerating all feature combinations. This capability makes FM particularly well-suited for recommendation problems such as predicting user-item interactions, including destination recommendations.

With 2,000 possible airport destinations, the target space is large and sparse. One-hot encoding further increases sparsity. Factorization Machines address this challenge by learning latent factors that capture relationships between features, even when many feature combinations are rarely observed.

Option A (CatBoost) is not an Amazon SageMaker built-in algorithm and therefore does not meet the requirement. Option B (DeepAR) is a time-series forecasting algorithm, not intended for recommendation or classification problems. Option D (k-means) is an unsupervised clustering algorithm and cannot directly predict a specific destination label.

AWS documentation explicitly lists recommendation systems and click prediction as primary use cases for the SageMaker Factorization Machines algorithm.

Therefore, Option C is the correct and AWS-verified choice.

This dataset shows severe class imbalance, with only 2% of records representing patients with the disease. AWS ML best practices recommend correcting imbalance only in the training dataset, while keeping validation and test sets representative of real-world distributions.

Synthetic Minority Oversampling Technique (SMOTE) generates synthetic samples of the minority class by interpolating between existing minority examples. This improves the model’s ability to learn disease-related patterns without discarding data.

PCA is a dimensionality reduction method, not an oversampling technique. Oversampling the majority class worsens imbalance. Altering the test dataset would invalidate evaluation results.

Therefore, applying SMOTE to the training dataset is the correct approach.

AWS enterprise ML best practices recommend using Amazon SageMaker Model Registry to manage models throughout their lifecycle. The Model Registry is designed specifically to catalog models, track versions, and associate metadata such as training metrics, approval status, and deployment history.

Model Registry introduces the concept of model groups, which act as logical containers for different versions of the same model. Each model version within a group automatically inherits versioning, metadata tracking, and governance controls. This eliminates the operational burden of manually managing model versions and ensures consistent lineage and traceability across development, testing, and production environments.

Option A is less optimal because manually tagging model versions increases operational complexity and does not take full advantage of the built-in version management features provided by model groups.

Options C and D are incorrect because Amazon ECR is a container image repository, not a model governance or lifecycle management service. Using ECR to manage ML model versions would require custom tooling and manual metadata handling, significantly increasing operational overhead.

By using model groups within SageMaker Model Registry, the company gains a centralized, scalable, and AWS-native solution for enterprise AI governance. This approach directly aligns with AWS documentation for managing model catalogs, version control, and metadata association while minimizing manual intervention.

Amazon SageMaker supports direct file system access for training jobs through Amazon FSx. AWS documentation states that FSx for NetApp ONTAP file systems can be mounted directly to SageMaker training instances when they are located in the same VPC.

Mounting the FSx file system allows SageMaker to stream large datasets efficiently without copying data into Amazon S3. This is ideal for very large datasets such as 6 TB of image data and avoids unnecessary storage duplication.

Options involving SageMaker Data Wrangler are intended for data preparation and exploration, not large-scale training data access. Mountpoint for Amazon S3 is not required and introduces additional complexity.

Therefore, Option A is the correct and AWS-aligned solution.

Class imbalance occurs when one class significantly outnumbers another, causing models to bias predictions toward the majority class. In this case, images without defects (1,800) vastly outnumber images with defects (200). AWS ML best practices recommend oversampling the minority class to improve class representation without discarding valuable data.

Oversampling techniques—such as duplicating minority samples or applying data augmentation—help the model better learn defect-related features. This approach preserves all available data and improves recall and precision for underrepresented defect classes.

Option B is incorrect because undersampling the minority class would further worsen imbalance. Option A unnecessarily reduces dataset size. Option D does not address the imbalance problem.

Thus, oversampling defect images is the correct solution.

Dynamic data masking allows you to control how sensitive data is presented to users at query time, without modifying or storing transformed versions of the source data. Amazon Redshift supports dynamic data masking, which can be implemented with minimal effort. This solution ensures that the data scientist can access the required information while sensitive data remains protected, meeting the requirements efficiently and with the least implementation effort.

Logging the metrics to Amazon CloudWatch allows the metrics to be tracked and monitored effectively.

CloudWatch Alarms can be configured to trigger when metrics breach a predefined threshold.

The alarm can be set to notify through Amazon Simple Notification Service (SNS), which can send email messages to the configured recipients.

This is the standard and most efficient way to achieve the desired functionality.

The primary goal is to produce the most complete dataset while handling missing values and extreme outliers appropriately. Dropping samples (Option A) or columns (Option D) would reduce data completeness and potentially remove valuable information, which contradicts the requirement.

Imputation is therefore the correct approach. Between mean and median imputation, AWS ML best practices recommend using the median when features contain outliers. The mean is sensitive to extreme values and can be skewed significantly, leading to imputed values that are not representative of the typical data distribution. In contrast, the median is robust to outliers, making it a better statistical estimator for central tendency in such datasets.

Amazon SageMaker Data Wrangler supports median imputation as a built-in transformation, enabling ML engineers to handle missing values consistently across large tabular datasets without custom code. This approach preserves all rows and columns while minimizing distortion caused by extreme values, which is particularly important for neural networks that are sensitive to input distributions.

Therefore, imputing missing values with the median value provides the most complete and statistically appropriate dataset for training.

For real-time anomaly detection on streaming data, AWS recommends using Amazon Managed Service for Apache Flink, which provides serverless, scalable stream processing with built-in ML functions.

Apache Flink includes a native RANDOM_CUT_FOREST (RCF) function for unsupervised anomaly detection. This eliminates the need to deploy, manage, or scale custom ML endpoints. When combined with Amazon Kinesis Data Streams, the solution can process thousands of records per second with very low latency.

Option B introduces multiple services and custom logic, increasing operational overhead. Option C requires managing EC2 infrastructure and Kafka clusters. Option D is batch-oriented and does not meet real-time requirements.

AWS documentation explicitly highlights Kinesis + Managed Flink + RCF as the lowest-overhead solution for real-time anomaly detection.

Therefore, Option A is the correct and AWS-aligned choice.

AWS Compute Optimizer analyzes the resource usage of Amazon EC2 instances, ECS services, Lambda functions, and Amazon EBS volumes. It provides actionable recommendations to optimize resource utilization and reduce costs, such as resizing instances, moving workloads to Spot Instances, or changing volume types. This solution requires the least development effort because Compute Optimizer is a managed service that automatically generates insights and recommendations based on historical usage data.

SageMaker JumpStart provides access to pre-trained models, including large language models (LLMs), which can be easily deployed and fine-tuned with a low-code/no-code (LCNC) approach. Using SageMaker Autopilot with JumpStart simplifies the fine-tuning process by automating model optimization and reducing the need for extensive coding, making it the ideal solution for this requirement.

Shadow testing allows you to send a copy of live production traffic to a shadow variant of the new model while keeping the existing production model unaffected. This enables you to evaluate the performance of the new model in real-time with live data without impacting end users. SageMaker endpoints support this setup by allowing traffic mirroring to the shadow variant, making it an ideal solution for assessing the new model's performance.

When Model Monitor identifies data quality issues, it might be due to a shift in the data distribution compared to the original baseline. By creating a new baseline using the most recent production data and updating Model Monitor to evaluate against this baseline, the ML engineer ensures that the monitoring is aligned with the current data patterns. This approach mitigates false positives and reflects the updated data characteristics without immediately retraining the model.

For cross-account Amazon S3 access, AWS requires two components:

An S3 bucket policy in the owning account (Account A) that grants access to a principal in another account

An IAM role policy in the consuming account (Account B) that allows the service to access the bucket

Amazon SageMaker training jobs assume an IAM role in the account where the job runs—in this case, Account B. Therefore, the IAM policy must be attached to the SageMaker execution role in Account B.

The S3 bucket policy must reside in Account A because bucket policies are owned and enforced by the bucket owner. This policy explicitly allows the IAM role from Account B to read the training data.

Any other combination fails either because the policy is in the wrong account or because the role is not the one used by SageMaker.

AWS documentation clearly describes this pattern as the correct way to grant cross-account access for SageMaker training jobs.

Therefore, Option B is the correct and AWS-aligned solution.

AWS recommends lifecycle configuration scripts as the simplest and most direct way to customize Amazon SageMaker Notebook Instances at creation time. Lifecycle configurations run automatically when a notebook instance is created or started, allowing scripts, packages, and system dependencies to be installed without manual intervention.

This approach is fully supported, requires no additional infrastructure, and integrates directly with the notebook creation workflow. The script can be reused across notebooks, ensuring consistency.

Options B, C, and D introduce unnecessary complexity, such as container management, private package repositories, or event-driven orchestration.

Therefore, lifecycle configuration scripts provide the least operational overhead solution.

AWS documentation recommends using RecordIO format with lazy loading to optimize data input pipelines for image-based training workloads. RecordIO is a binary data format that enables sequential reads, reducing I/O overhead and improving throughput during training.

By converting JPEG images into RecordIO format, the training job can read data more efficiently from Amazon S3. Lazy loading ensures that only the required data is loaded into memory when needed, which optimizes CPU utilization during computationally intensive preprocessing steps.

Option A (file mode) results in many small S3 GET requests, which can become a bottleneck for large image datasets. Option B changes training behavior and can negatively affect convergence and performance. Option C reduces image quality, which directly impacts model accuracy and violates the requirement.

AWS SageMaker documentation explicitly highlights RecordIO and lazy loading as best practices for high-performance image training pipelines, especially when preprocessing is CPU-intensive.

Therefore, Option D is the correct and AWS-aligned solution.

Monitoring bias drift in deployed machine learning models is crucial to ensure fairness and accuracy over time. Amazon SageMaker Clarify provides tools to detect bias in ML models, both during training and after deployment. To monitor bias drift for models deployed to real-time endpoints, an effective approach involves orchestrating SageMaker Clarify jobs using AWS Lambda functions.

Implementation Steps:

Set Up Data Capture:

Enable data capture on the SageMaker endpoint to record input data and model predictions. This captured data serves as the basis for bias analysis.

Develop a Lambda Function:

Create an AWS Lambda function configured to initiate a SageMaker Clarify job. This function will process the captured data to assess bias metrics.

Schedule or Trigger the Lambda Function:

Configure the Lambda function to run on-demand or at scheduled intervals using Amazon CloudWatch Events or EventBridge. This setup allows for regular bias monitoring as per the application's requirements.

Analyze and Respond to Results:

After each Clarify job completes, review the generated bias reports. If bias drift is detected, take appropriate actions, such as retraining the model or adjusting data preprocessing steps.

Advantages of This Approach:

Automation: Utilizing AWS Lambda for orchestrating Clarify jobs enables automated and scalable bias monitoring without manual intervention.

Cost-Effectiveness: AWS Lambda's serverless nature ensures that you only pay for the compute time consumed during the execution of the function, optimizing resource usage.

Flexibility: The solution can be tailored to specific monitoring needs, allowing for adjustments in monitoring frequency and analysis parameters.

By implementing this solution, the company can effectively monitor bias drift in real-time, ensuring that the AI application maintains fairness and accuracy throughout its lifecycle.

A sudden drop in model performance after a long period of stability is a classic indicator of data drift. According to AWS ML documentation, production data distribution drift occurs when the statistical properties of incoming data change over time compared to the training dataset.

This drift can be caused by changes in user behavior, market conditions, seasonal trends, or upstream data pipelines. When drift occurs, the model’s learned patterns no longer align with real-world data, leading to degraded accuracy and other performance metrics.

Lack of training data (Option A) and overfitting (Option D) are issues that typically manifest during initial training, not after months of stable production performance. Compute constraints (Option C) may affect latency but do not usually cause sustained accuracy degradation.

AWS recommends using SageMaker Model Monitor to detect such drift and trigger retraining workflows.

Therefore, drift in the production data distribution is the most likely cause of the observed performance degradation.

Amazon Kendra Experience Builder provides a fully managed, low-code solution for building conversational search and question-answering applications. AWS documentation states that Kendra natively supports semantic search, vector embeddings, and vector-based retrieval, making it well suited for RAG-style applications with minimal development effort.

When integrated with Amazon Bedrock, Kendra can act as the retrieval layer, handling document ingestion, indexing, embedding generation, and relevance ranking automatically. This eliminates the need to manually manage embedding models, vector databases, and search logic.

Options B and C require custom schema design, vector indexing, query logic, and operational management of PostgreSQL instances. Although pgvector supports vector search, it significantly increases development and maintenance effort. Option D is unrelated to vector search and is used only for metadata cataloging.

AWS explicitly positions Amazon Kendra as the fastest way to build enterprise-grade conversational assistants that integrate with foundation models.

Therefore, Option A is the correct and most AWS-aligned solution.

In a Retrieval Augmented Generation (RAG) architecture, retrieval quality directly impacts response accuracy. AWS documentation for Bedrock and OpenSearch highlights the use of reranker models to improve relevance after initial vector search retrieval.

Vector search retrieves documents based on embedding similarity, but the top results are not always the most contextually relevant. A reranker model evaluates the retrieved documents against the user query and reorders them based on semantic relevance before sending them to the foundation model.

Option A improves readability but does not improve retrieval relevance. Option C filters data before retrieval, which can reduce recall. Option D improves performance, not relevance.

AWS explicitly recommends reranking as a best practice for improving answer quality in RAG systems.

Therefore, Option B is the correct solution.

SageMaker Asynchronous Inference is designed for long-running inference workloads and large payloads (up to 1 GB). Requests are queued, processed asynchronously, and results are written to Amazon S3.

Real-time endpoints have payload and timeout limits. EC2 and ECS require infrastructure management, increasing operational overhead.

AWS documentation explicitly recommends asynchronous inference for workloads with large inputs and long execution times.

Therefore, Option C is the correct and most efficient solution.

In Amazon SageMaker AI, identifying bias in machine learning datasets before model training is a critical step to ensure fairness and reliability of predictions. This process is referred to as pre-training bias analysis, and it focuses on understanding whether the training data itself introduces bias—particularly through imbalanced class labels or sensitive attributes.

The Difference in Proportions of Labels (DPL) is a pre-training bias metric specifically designed to measure class imbalance. DPL compares the proportion of a specific label (such as a positive outcome) across different groups or classes within a dataset. If one class or group is overrepresented relative to another, the DPL value will deviate significantly from zero, clearly indicating imbalance. AWS documentation highlights DPL as a key metric used by SageMaker Clarify to detect label imbalance prior to model training.

By contrast, Mean Squared Error (MSE) is a regression evaluation metric used after model training to measure prediction error, not dataset bias. Silhouette score is an unsupervised learning metric used to evaluate clustering quality, making it irrelevant for supervised classification bias detection. Structural Similarity Index Measure (SSIM) is an image-quality metric used in computer vision tasks and has no application in dataset bias analysis.

Using DPL allows ML engineers to proactively detect and address skewed label distributions—such as by re-sampling, re-weighting, or collecting additional data—before training begins. This aligns with AWS best practices for responsible AI and helps reduce the risk of biased predictions that could negatively impact real-world decision-making.

Therefore, Difference in Proportions of Labels (DPL) is the correct and AWS-recommended metric for confirming class imbalance during pre-training bias analysis in Amazon SageMaker AI.

This use case involves large payloads (high-resolution images), variable processing time, and a requirement to notify users upon completion. AWS documentation recommends Amazon SageMaker asynchronous inference for exactly this scenario.

Asynchronous inference allows clients to submit inference requests without waiting for a response. The request payload is stored in Amazon S3, and the inference result is written back to S3 when processing is complete. This approach is designed for workloads that cannot meet real-time latency requirements and where payload sizes exceed real-time limits.

SageMaker asynchronous inference integrates natively with Amazon SNS to send notifications when inference completes or fails, which directly satisfies the user notification requirement.

Batch transform jobs are intended for offline, scheduled processing of large datasets and do not provide built-in user notification mechanisms. Amazon EFS is not required because SageMaker natively integrates with S3 for inference input and output.

AWS explicitly documents asynchronous inference as the preferred solution for large image inference with completion notifications.

Therefore, Option B is the correct and AWS-verified answer.

To implement a manual approval-based workflow ensuring that only approved models are deployed to production endpoints, Amazon SageMaker provides integrated tools such as SageMaker Pipelines and the SageMaker Model Registry.

SageMaker Pipelines is a robust service for building, automating, and managing end-to-end machine learning workflows. It facilitates the orchestration of various steps in the ML lifecycle, including data preprocessing, model training, evaluation, and deployment. By integrating with the SageMaker Model Registry, it enables seamless tracking and management of model versions and their approval statuses.

Implementation Steps:

Define the Pipeline:

Create a SageMaker Pipeline encompassing steps for data preprocessing, model training, evaluation, and registration of the model in the Model Registry.

Incorporate a Condition Step to assess model performance metrics. If the model meets predefined criteria, proceed to the next step; otherwise, halt the process.

Register the Model:

Utilize the RegisterModel step to add the trained model to the Model Registry.

Set the ModelApprovalStatus parameter to PendingManualApproval during registration. This status indicates that the model awaits manual review before deployment.

Manual Approval Process:

Notify the designated approver upon model registration. This can be achieved by integrating Amazon EventBridge to monitor registration events and trigger notifications via AWS Lambda functions.

The approver reviews the model's performance and, if satisfactory, updates the model's status to Approved using the AWS SDK or through the SageMaker Studio interface.

Deploy the Approved Model:

Configure the pipeline to automatically deploy models with an Approved status to the production endpoint. This can be managed by adding deployment steps conditioned on the model's approval status.

Advantages of This Approach:

Automated Workflow: SageMaker Pipelines streamline the ML workflow, reducing manual interventions and potential errors.

Governance and Compliance: The manual approval step ensures that only thoroughly evaluated models are deployed, aligning with organizational standards.

Scalability: The solution supports complex ML workflows, making it adaptable to various project requirements.

By implementing this solution, the company can establish a controlled and efficient process for deploying models, ensuring that only approved versions reach production environments.