Final answer:
The correct command to create a new Docker network for containers to use called 'mynet' is 'docker network create mynet'.
Step-by-step explanation:
The correct command to create a new Docker network for containers to use called 'mynet' is option A) docker network create mynet. This command creates a network with the name 'mynet' that can be used by containers. Here's an example:
docker network create mynet