SageMaker script mode allows ML engineers to bring existing training scripts written for frameworks such as PyTorch and TensorFlow directly into SageMaker with minimal changes. AWS documentation explicitly states that script mode is designed to support migration of existing ML workloads.

With script mode, the user provides a custom training script, and SageMaker handles infrastructure provisioning, distributed training, logging, and model artifact storage. This makes script mode ideal for companies that want to reuse established codebases without rewriting them.

Built-in algorithms require adopting AWS-provided implementations. SageMaker Canvas is a no-code tool, and JumpStart provides pretrained models and templates but does not focus on custom script reuse.

Therefore, Option D is the correct and AWS-recommended choice.

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.

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 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.

Option A is correct because Amazon Rekognition provides a built-in EyeDirection attribute that indicates the direction a person’s eyes are gazing, expressed through pitch and yaw. AWS documentation describes EyeDirection as showing where the eyes are looking independently of head pose. For a driver-monitoring use case, this is directly useful for identifying whether a driver is looking away from the road and may be distracted.

AWS also announced that Rekognition’s eye gaze direction detection is intended to support safety use cases and to help identify where users focus their attention. That makes it a strong match for monitoring in-vehicle cameras for distraction detection. Because Rekognition is a fully managed service with ready-to-use computer vision capabilities, it requires far less operational effort than collecting data, labeling it, training a custom model in SageMaker, and maintaining that model over time.

The other options are less appropriate. Option B could work technically, but building and maintaining a custom SageMaker model would require significantly more engineering and operational work than using a managed Rekognition feature. Option C introduces unnecessary complexity by adding a third-party system when AWS already provides a directly relevant managed capability. Option D is unrelated because Amazon Comprehend analyzes text, while the input here is camera footage. Since the question asks for the solution with the least operational effort , the best AWS-aligned answer is to use the managed Rekognition eye gaze detection capability. Therefore, the fully verified answer is A .

The key requirements in this scenario are variable traffic patterns and cost efficiency. The workload has unpredictable spikes during evenings and weekends, followed by long periods of low or no usage. According to AWS Machine Learning documentation, Amazon SageMaker Serverless Inference is specifically designed for such use cases.

SageMaker Serverless Inference automatically provisions, scales, and shuts down compute resources based on incoming inference requests. Customers are billed only for the compute time used during inference, not for idle resources. This makes it highly cost-effective for workloads with intermittent or spiky traffic, such as real-time chat moderation in gaming environments.

Option A is incorrect because batch transform jobs are intended for offline, large-scale inference and require fixed capacity during job execution. They are not suitable for real-time NLP moderation.

Option C is also incorrect because reserving an EC2 GPU instance incurs continuous costs regardless of utilization. This would be inefficient given the long idle periods described in the scenario.

Option D, SageMaker Asynchronous Inference, is designed for workloads with long processing times or large payloads and still requires endpoint provisioning. While it can handle traffic spikes, it does not scale down to zero in the same cost-efficient manner as Serverless Inference.

Therefore, Amazon SageMaker Serverless Inference is the most cost-effective and operationally efficient solution for deploying an NLP moderation model with highly variable usage patterns.

The requirement is event-driven automation when new data arrives in Amazon S3, followed by training and model registration. Amazon EventBridge natively supports S3 object creation events and can trigger downstream workflows immediately.

By using EventBridge to start an AWS Step Functions workflow that includes a training step and a SageMaker Model Registry registration step, the pipeline runs automatically as soon as new data is uploaded—well within the 24-hour requirement.

Option A introduces unnecessary polling and delay. Option B is time-based and does not ensure alignment with data readiness. Option C is invalid because S3 Lifecycle rules manage object transitions, not workflow execution.

Therefore, EventBridge-triggered Step Functions is the correct solution.