Which protocol is used for communication between Cisco Unity Express and Cisco Unified
Communications Manager Express?

A.
H.323

B.
G.711

C.
MGCP

D.
Q.931

E.
SIP

Explanation:
Link:
http://www.cisco.com/en/US/docs/voice_ip_comm/unity_exp/rel8_5/install/prereq.html#wp1112818