Apache Parquet is a columnar storage file format optimized for complex and large datasets. It provides efficient reading and processing by accessing only the required columns, which reduces I/O and speeds up data handling. This makes it ideal for use with Amazon SageMaker Canvas, where minimizing processing time is important for training ML models. Parquet is also compatible with S3 and widely supported in data analytics and ML workflows.

The correct answer is C. Class imbalance ratio.

Amazon SageMaker Clarify provides both pre-training and post-training bias detection capabilities to help data scientists ensure fairness in ML models. Pre-training bias metrics specifically analyze the training dataset to detect underrepresentation of certain groups or features before a model is trained. The class imbalance ratio measures how evenly different classes or sensitive attributes are represented in the dataset. A high imbalance indicates that a particular segment of customers (e.g., certain age groups, genders, or ethnicities) may be underrepresented, which could lead to biased predictions when the model is deployed.

Feature attribution bias (Option B) and prediction distribution skew (Option A) are post-training metrics. Feature attribution bias evaluates whether the model relies disproportionately on certain features for predictions, while prediction distribution skew examines whether the model’s outputs are skewed for specific groups. Model performance gap (Option D) is also a post-training measure, focusing on differences in accuracy or other performance metrics between groups.

By using the class imbalance ratio during pre-training analysis, the company can identify and mitigate underrepresentation before training the model. Actions may include resampling the dataset, weighting underrepresented classes, or applying synthetic data augmentation to ensure that the model is trained on a balanced, fair dataset. This aligns with AWS best practices for ML solution monitoring, maintenance, and security, particularly for responsible AI and fairness assessment.

In summary, the class imbalance ratio allows proactive bias detection at the dataset level, preventing unfair recommendations and ensuring equitable treatment across all customer segments in the recommendation system.

Accuracy measures the proportion of correctly predicted labels (both positive and negative) out of the total predictions. It is the appropriate metric when the goal is to maximize the correct predictions of both positive and negative labels. However, it assumes that the classes are balanced; if the classes are imbalanced, other metrics like precision, recall, or specificity may be more relevant depending on the specific needs.

Option A is correct because AWS Glue provides the lowest-overhead managed pattern for this scenario: use a crawler to keep the AWS Glue Data Catalog updated for the S3 dataset, then use AWS Glue Data Quality to evaluate rules against that cataloged data. AWS documentation states that crawlers can automatically discover and catalog new or updated S3 data sources, reducing manual metadata management overhead. AWS Glue Data Quality is also documented as a managed, serverless capability for measuring and monitoring data quality.

This option is especially strong because the dataset is already in Amazon S3 and partitioned by date, and the requirement is simply to automatically check quality before the data is sent to QuickSight. AWS Glue Data Quality supports the Data Catalog as an entry point, and AWS documentation notes that this approach is intended for datasets that are already cataloged and for ongoing governance-style quality evaluation. The docs also show that scheduling is supported for Data Catalog-based quality checks. That means the company can run the crawler monthly, then evaluate a ruleset against the cataloged table without needing custom ETL code.

The other options add more operational work. Option B requires a custom PySpark job and custom functions, which is more maintenance-heavy than using catalog-based quality rules directly. Option C depends on bespoke Lambda scripts. Option D does not use the right service for data quality validation. Because the question asks for the least operational overhead, the most AWS-aligned answer is A: monthly Glue crawler plus Glue Data Quality rules.

SageMaker script mode allows you to bring existing custom Python scripts and run them on AWS with minimal changes. SageMaker provides prebuilt containers for ML frameworks like PyTorch, simplifying the migration process. This approach enables the company to leverage their existing Python scripts and domain knowledge while benefiting from the scalability and managed environment of SageMaker. It requires the least effort compared to building custom containers or retraining models from scratch.

Amazon EC2 Spot Instances provide unused compute capacity at discounts of up to 90%. AWS documentation strongly recommends Spot Instances for interruptible workloads such as long-running ML training jobs that can resume from checkpoints.

By enabling automatic checkpointing, SageMaker saves model state periodically to Amazon S3. If the Spot Instance is interrupted, training can resume with minimal loss of progress.

Reserved Instances and Savings Plans require long-term commitment and are not as cost-effective for sporadic workloads. On-Demand Instances are the most expensive option.

Therefore, Option D is the most cost-effective solution.

When GPU resources are limited and the hyperparameter search space is large, AWS documentation strongly recommends Bayesian optimization combined with early stopping. Bayesian optimization uses past evaluation results to intelligently select the next set of hyperparameters to test, focusing exploration on promising regions of the search space rather than testing all combinations.

In Amazon SageMaker, Bayesian optimization is the default and recommended strategy for hyperparameter tuning jobs. It significantly reduces the number of training runs required compared to grid or random search, making it highly cost-efficient for deep learning workloads.

Early stopping further improves efficiency by terminating training jobs that show poor validation performance in early epochs. This prevents wasted GPU time on configurations that are unlikely to perform well. AWS explicitly documents early stopping as a key feature for controlling training cost and duration.

Grid search and exhaustive search are computationally expensive and impractical for large hyperparameter spaces. Manual tuning is slow, error-prone, and does not scale.

By combining Bayesian optimization with early stopping, the company can rapidly converge on high-performing hyperparameter configurations while minimizing resource usage.

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

Scenario: The company needs to run a batch job for 90 minutes every weekend over the next 6 months. The processing can handle interruptions, and cost-effectiveness is a priority.

Why Spot Instances?

Cost-Effective: Spot Instances provide up to 90% savings compared to On-Demand Instances, making them the most cost-effective option for batch processing.

Interruption Tolerance: Since the processing can tolerate interruptions, Spot Instances are suitable for this workload.

Batch-Friendly: Spot Instances can be requested for specific durations or automatically re-requested in case of interruptions.

Steps to Implement:

Create a Spot Instance Request:

Use the EC2 console or CLI to request Spot Instances with desired instance type and duration.

Use Auto Scaling: Configure Spot Instances with an Auto Scaling group to handle instance interruptions and ensure job completion.

Run the Batch Job: Use tools like AWS Batch or custom scripts to manage the processing.

Comparison with Other Options:

Reserved Instances: Suitable for predictable, continuous workloads, but less cost-effective for a job that runs only once a week.

On-Demand Instances: More expensive and unnecessary given the tolerance for interruptions.

Dedicated Instances: Best for isolation and compliance but significantly more costly.

Amazon Macie is a fully managed data security and privacy service that uses machine learning to discover and classify sensitive data in Amazon S3. It is purpose-built to identify sensitive data with minimal operational overhead. After identifying the sensitive data, you can use AWS Lambda functions to automate the process of removing or redacting the sensitive data, ensuring efficiency and integration with the hybrid cloud environment. This solution requires the least development effort and aligns with the requirement to handle sensitive data effectively.

Provide flight departure, arrival, and delay information, and provide updates for low-latency workloads→ Real-time inference

Advertise holiday travel promotional deals to millions of users in multiple markets before holiday seasons for spiky workloads→ Serverless inference

Generate quarterly and annual flight reports and insights for trend analysis of large datasets→ Batch inference

Generate online image and audio stories for passengers to watch or listen to while waiting at an airport→ Asynchronous inference

The correct mapping depends on latency requirement, traffic pattern, payload size, processing duration, and whether the workload needs a persistent endpoint.

Real-time inference is the right choice for flight departure, arrival, and delay updates because this is an online user-facing workload that requires low latency. AWS states that SageMaker real-time inference is ideal for online inference workloads with low-latency or high-throughput requirements and uses a persistent fully managed endpoint. That fits flight status information because passengers and airline systems expect immediate responses.

Serverless inference is the best choice for holiday promotional deals because this traffic is spiky, seasonal, and unpredictable. AWS describes SageMaker Serverless Inference as suitable for intermittent or unpredictable traffic patterns. It is cost-effective because SageMaker manages the infrastructure and scales down when there are no requests, so the company does not pay for idle endpoint capacity.

Batch inference is correct for quarterly and annual flight reports because this workload analyzes large datasets offline and does not need an always-running endpoint. AWS says SageMaker batch transform is used to get inferences from large datasets and when a persistent endpoint is not required. Reports and trend analysis are scheduled, non-real-time analytics workloads, so batch inference is the most cost-effective option.

Asynchronous inference is the right choice for generating online image and audio stories. These requests can have larger payloads and longer processing times than normal low-latency API calls. AWS states that SageMaker Asynchronous Inference queues incoming requests and is ideal for large payloads, long processing times, and near-real-time latency requirements. Image and audio generation can take seconds or minutes, so asynchronous inference is more appropriate than real-time inference.