Which two statements about the digest and mac commands are true? (Choose two.)

A.
The mac command can use the Digital Encryption Standard (DES) in cipher-block chained (CBC) mode. The digest command can NOT.

B.
The mac command uses a distinct class of hash functions called message authentication codes (MACs). MAC functions combine the input file with a key supplied by the user, returning a fixed length digest.

C.
The mac command uses a distinct class of hash functions called MACs. A MAC function combines the input file with a randomly generated salt, and returns a digest.

D.
The digest command requires that the user supply a key. The mac command does NOT. The digest command takes an input file, combines it with the key, and a variable length digest is returned.