Which of the Following Describes a Pocket Veto

Which of the following describes a pocket veto?

A) Congress submits a bill to the president, but the president does not sign the bill within 10 days.
B) The president vetoes a bill from Congress. Congress then holds a vote but does not have a quorum.
C) Congress submits a bill to the president and then adjourns. The president does not sign the bill within 10 days.
D) The president vetoes a bill from Congress. Congress then holds a vote, but the bill does not pass.