A solutions architect manages a containerized application that is deployed on Amazon ECS.

AWS Secrets Manager is the best fit because it is built specifically to store, manage, and rotate secrets such as database credentials. AWS documentation states that Secrets Manager supports automatic rotation for supported secret types and reduces the need for custom credential-rotation code. KMS encrypts keys and data but is not itself a secret-rotation store. Parameter Store can hold secure strings, but Secrets Manager is the AWS service purpose-built for secret lifecycle management and scheduled rotation. Because the question asks for the least development effort, using Secrets Manager with automatic rotation is the most direct and operationally efficient solution.

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