Refer to the exhibit.

SH3 and SH4 are able to optimize FTP and HTTP sessions between Client41 and the respective application
hosts Server31 and Server32. However, optimization seems to be a problem for Client42 and these application
hosts. A quick check on SH3 and SH4 registers neither optimized nor pass-through traffic from Client42.
Client42 is able to ping to both Server31 and Server32. Note that SH3 and SH4 are in auto-discovery mode.
What is the likely cause?

A.
The default gateway of Client41 is configured wrong

B.
The default gateway of Client42 is configured wrong

C.
An outbound access-list specified at R3f0 denies TCP traffic from Client42

D.
The routing protocol between R3 and R4 is configured wrong