What command allows you to attach to a running container's terminal?

The command that allows you to attach to a running container's terminal is the one that uses "docker attach" followed by the container ID. This command connects your terminal to the standard input, output, and error streams of the specified container, enabling you to interact with its running process directly. This is particularly useful for viewing real-time output or providing input to interactive applications that are running within the container.

Using "docker exec" allows you to run a new command in a specific container, opening a new terminal session, which is useful for executing commands but does not attach to the existing process. The option "docker connect" does not exist in Docker’s command-line interface; hence, it cannot be used for attaching to a container. Similarly, "docker link" is an outdated command that was primarily used for linking containers, and it does not relate to accessing the terminal of a running container. Thus, "docker attach [container_id]" is the appropriate command for the task described.