Which statement about AAR functionality is true?
A. AAR reroutes calls through the PSTN upon WAN failure.
B. AAR reroutes calls through the PSTN when Cisco Unified Communications Manager CAC blocks a call.
C. AAR reroutes calls through the WAN when the PSTN connection fails.
D. AAR reroutes calls to another phone number when a Cisco IP Phone unregisters.
