Which ability does the Survivable Remote Site Telephony feature provide?

Which ability does the Survivable Remote Site Telephony feature provide?

A.
a means to allow the local site to continue to send and receive calls in the event of a WAN failure

B.
a means to route calls on-net through other sites during high utilization periods

C.
a method that allows for backup calls in the event that your gateway fails

D.
the ability to force a call out of a certain trunk when the Cisco Unified Communications Manager
is being upgraded

Explanation: