What is the port number of the IPsec Authentication Header packet?

A.
IP protocol 50

B.
TCP port 51

C.
UDP port 50

D.
IP protocol 51

E.
UDP port 51

F.
TCP port 50

Explanation:
6.2. Managed Security services traversing the core
AH operates directly on top of IP, using IP protocol number 51.
ESP operates directly on top of IP, using IP protocol number 50.