The Difference Between a Pocket Veto and an Ordinary Veto

The difference between a pocket veto and an ordinary veto is that with the pocket veto, the president:

A) Can't prevent Congress from overriding him if it wishes to do so
B) Only threatens to reject a bill of which he doesn't approve
C) Fails to sign a bill and lets it die during the last days of a congressional session
D) Rejects the specific portion of a bill with which he doesn't agree