Which two statements are true of a network mask?

Which two statements are true of a network mask? (Choose two)

A.
A subnet mask specifies the portion of an IP address that is in a binary format

B.
A subnet mask specifies the portion of an IP address that is in a decimal format

C.
A subnet mask specifies the portion of an IP address that represents a network prefix

D.
A subnet mask specifies the portion of an IP address that represetns network hosts