Amazon MLA-C01 Dumps - Pass AWS Certified Machine Learning Engineer - Associate Exam in 2026

This is a classic class imbalance problem, where fraudulent transactions (minority class) are severely underrepresented. AWS documentation for SageMaker Data Wrangler recommends SMOTE (Synthetic Minority Oversampling Technique) as an effective approach for improving model performance in such scenarios.

SMOTE generates synthetic minority samples by interpolating between existing minority class examples. This improves the model's ability to learn decision boundaries without simply duplicating data, which can cause overfitting.

Random undersampling removes valuable majority class data, reducing overall model robustness. Random oversampling duplicates data and increases overfitting risk. Changing algorithms does not address the root cause.

AWS best practices highlight SMOTE as the preferred technique for fraud detection and other highly imbalanced datasets.

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

Hyperband is a hyperparameter tuning strategy designed to minimize computation time by adaptively allocating resources to promising configurations and terminating underperforming ones early. It efficiently balances exploration and exploitation, making it ideal for large datasets and deep learning models where training can be computationally expensive.

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.

Recall measures the ability of a model to correctly identify all positive cases (true positives) out of all actual positives, minimizing false negatives. Since the cost of false negatives is much higher than false positives in this scenario, the ML engineer should prioritize models with high recall to reduce the likelihood of missing positive cases.

Amazon SageMaker AI automatically collects aggregated metadata from training jobs to improve service reliability, performance, and operational insights. This metadata can include information such as algorithm usage, instance types, resource utilization, and job configuration details. However, AWS documentation clearly states that customers can opt out of SageMaker metadata collection to meet regulatory or compliance requirements.

SageMaker provides a supported mechanism to disable metadata tracking at the training job level. By explicitly opting out of metadata tracking when submitting training jobs---either through the AWS Management Console, AWS CLI, or SDK---the service will stop collecting aggregated metadata for those jobs. This option is specifically designed for customers with strict compliance, data residency, or regulatory constraints.

Option B is incorrect because running training jobs in a private subnet within a custom VPC controls network isolation, not service-level telemetry or metadata collection. Metadata collection occurs at the SageMaker service layer and is independent of VPC configuration.

Option C is also incorrect because encrypting training data with a customer-managed AWS KMS key protects data at rest and in transit but does not prevent SageMaker from collecting operational metadata about training jobs.

Option D is incorrect because AWS Nitro instances provide enhanced security and performance isolation at the infrastructure level but have no impact on SageMaker's metadata collection mechanisms.

Therefore, opting out of metadata tracking for training jobs is the only solution that directly addresses the compliance requirement and is explicitly supported by AWS documentation.