Refer to the exhibit.

On R1, encrypt counters are incrementing. On R2, packets are decrypted, but the
encrypt counter is not being incremented. What is the most likely cause of this issue?

A.
a routing problem on R1

B.
a routing problem on R2

C.
incomplete IPsec SA establishment

D.
crypto engine failure on R2

E.
IPsec rekeying is occurring