Which statement about configuring the Cisco VCS Control and Cisco VCS Expressway is true?
A. You do not need to configure search rules for traversal calls.
B. You need to configure the firewall to allow communication from the Cisco VCS Expressway to the Cisco VCS Control.
C. The username on the Cisco VCS Control and Cisco VCS Expressway are local and do not need to match.
D. The Cisco VCS Expressway is the Traversal Server.
Answer D is correct, but why does answer B not ?.