An IoT company trains and tests an XGBoost object-detection model in Amazon SageMaker and needs to track performance metrics across hyperparameter variants. The engineers also need to send SMS notifications after each training job completes. Which combination of AWS services meets these needs?

Amazon CloudWatch is the correct service for monitoring performance metrics because it collects and tracks metrics, collects and monitors log files, and sets alarms. This allows engineers to track performance across hyperparameter variants. Amazon Simple Notification Service (SNS) is the correct choice for sending SMS notifications. SNS is a fully managed messaging service that enables you to decouple microservices, distributed systems, and serverless applications. It supports sending messages to various endpoints, including SMS, email, and AWS Lambda functions. Amazon SQS is incorrect for notifications because it is a message queuing service, not a direct notification service. AWS CloudTrail is incorrect for monitoring performance metrics because it focuses on auditing AWS API calls and user activity, not application or model performance.