Which service would you use to manage a large number of Docker containers?

The correct choice for managing a large number of Docker containers is Amazon ECS (Elastic Container Service). ECS is a highly scalable, high-performance container orchestration service that supports Docker containers and allows you to easily run and manage applications in a clustered environment.

With ECS, users can efficiently deploy and manage containerized applications while using AWS's infrastructure. It provides features such as load balancing, service discovery, and integrated monitoring, which are essential for managing multiple containers effectively. This makes it ideal for applications that require scaling and dynamic allocation of resources based on demand.

In contrast, while Amazon EC2 provides the underlying infrastructure for running virtual servers (which can include Docker containers), it does not offer specialized container management capabilities. AWS Lambda is designed for running code in response to events without managing servers, and it doesn't support Docker containers in the way that ECS does. Amazon S3 is a storage service primarily used for storing and retrieving data rather than managing containerized applications. Thus, ECS is specifically built to streamline the management of Docker containers, making it the best choice for this scenario.