An administrator is setting up a repository to hold the company's container images and must apply a lifecycle rule that automatically deletes images with a particular tag when they are older than 15 days. Which option provides the required behavior with the greatest operational efficiency?

The correct option is to create a repository in Amazon Elastic Container Registry (ECR) and add a lifecycle policy. Amazon ECR is a fully managed Docker container registry that makes it easy to store, manage, and deploy Docker container images. ECR lifecycle policies allow you to automatically delete images based on criteria such as age (e.g., older than 15 days) and tags, directly addressing the requirement for operational efficiency. AWS CodeArtifact is a managed artifact repository service that supports package formats like Maven, npm, and PyPI, but not Docker container images. Amazon S3 can store container images as objects, but it lacks native support for container image management and specific lifecycle rules based on image tags, making it less operationally efficient for this use case. EC2 Image Builder is used to automate the creation, management, and deployment of customized, secure, and up-to-date server images, not for managing container image repositories or applying lifecycle rules to existing images.