An organization wants to schedule a retraining pipeline to run every Sunday night. Which AWS service should they use to trigger the pipeline on a schedule?
Amazon EventBridge provides cron and rate expressions that trigger targets on a defined schedule, satisfying the Sunday-night recurrence requirement without a running server. Its rule-based event bus invokes the pipeline directly, so no polling or manual invocation is needed, and it integrates natively with AWS pipeline services.
Why this answer
Amazon EventBridge is the correct choice because it provides a scheduled event source using cron or rate expressions to trigger target services at specified times, such as every Sunday night. It can directly invoke an AWS Step Functions state machine or a Lambda function to start the retraining pipeline, making it the native scheduling service for event-driven workflows in AWS.
Exam trap
The trap here is that candidates often confuse AWS Lambda's ability to be triggered by a schedule with Lambda itself being a scheduling service, but Lambda is only the compute target, not the scheduler — EventBridge is the service that provides the scheduled trigger.
How to eliminate wrong answers
Option A is wrong because AWS Lambda is a compute service that runs code in response to triggers, but it does not natively provide scheduling capabilities; while you can use Lambda with EventBridge, Lambda alone cannot generate scheduled events. Option B is wrong because AWS Step Functions is a workflow orchestration service that coordinates multiple AWS services, but it does not have built-in scheduling; it requires an external trigger like EventBridge to start execution on a schedule. Option C is wrong because Amazon SQS is a message queue service for decoupling application components, not a scheduling service; it cannot trigger pipelines on a schedule and relies on consumers to poll or receive messages.