The correct service is a content delivery network that offers the ability to cache content close to end-users and can be customized to cache based on request details, including headers. Amazon Simple Storage Service (S3) is primarily an object storage service without built-in caching features. AWS Lambda is a serverless computing platform that runs code in response to events and does not provide caching. Elastic Load Balancing automatically distributes incoming application traffic across multiple targets, but it is not responsible for content caching.