Refer to the exhibit. What might be the reason of these failed attempts in ACS? 

Answer options:

A. The wrong shared secret is configured on the AAA client or ACS.
B. The request is coming from a AAA client that is configured only for RADIUS on ACS.
C. The request is coming from a AAA client that is configured only for TACACS+ on ACS.
D. The PC that is trying to access the device is outside the known subnet.

B