Which description is correct about authentication headers (AH)?

Which description is correct about authentication headers (AH)?

A.
The authentication information is a keyed hash based on all of the bytes in the packet.

B.
The authentication information may be the same on different packets if the integrity remains in place.

C.
The authentication information hash will increase by one if the bytes remain the same on transfer.

D.
The authentication information hash will remain the same if the bytes change on transfer.