A Cisco Unified Communications Manager cluster is installed in headquarters only.
How can international calls be blocked while national calls are allowed for branch office Cisco IP Phones during a WAN failure?

A.	Configure CSS and partitions in Cisco Unified Communications Manager and apply the CSS and partitions to the SRST ISR
B.	Configure CSS and partitions in the SRST ISR
C.	Configure COR in the SRST ISR.
D.	Configure voice translations in the SRST ISR.