What is the difference between an SELinux domain and an SELinux type?

What is the difference between an SELinux domain and an SELinux type?

A.
A domain is a group of SELinux types.

B.
A domain defines the range of access that an object has. A type is used to define an access level.

C.
A domain is assigned to processes while a type is assigned to objects such as files and directories.

D.
A domain is an alternative keyword for type.