Which three of the following are steps in configuring MGCP Fallback and Cisco Unified SRST?
(Choose three)

A.
Define the SRST reference for phones in the Device Pool configuration

B.
Enable and configure the MGCP fallback and Cisco Unified SRST features on the IOS gateways.

C.
Implement a simplified SRST dial plan on the remote-site-gateways to ensure connectivity for
remote-site phones in SRST mode.

D.
Enable SIP trunking between both remote and hub sites to provide mesh coverage.

E.
Define the SRST reference in the configuration on the IP Phones.

F.
Enable and configure the MGCP fallback on the IOS gateway but not Cisco Unified SRST since it is
enabled automatically.