You are trying to add Cisco VCS to Cisco TMS, but the addition is failing. Which three scenarios might be causing this failure?

A.	Cisco TMS is running a version earlier than 12.5.
B.	Cisco TMS was not upgraded before adding Cisco VCS.
C.	Cisco TMS and Cisco VCS do not have synchronized time settings.
D.	SNMP is not enabled on Cisco VCS.
E.	UDP port 161 is blocked on the network.
F.	The management address on Cisco VCS does not match the Cisco TMS IP address.