Which of the following is NOT a feature or quality of a hash function?

Which of the following is NOT a feature or quality of a hash function?

A.
Encrypted with the sender’s RSA private key, the hash function forms the digital signature.

B.
It is mathematically infeasible to derive the original message from the message digest.

C.
The hash function forms a two-way, secure communication.

D.
The hash function is irreversible.

E.
It is mathematically infeasible for two different messages to produce the same message digest.