Which interface in the Cisco Unified Contact Center Enterprise solution is supported over a firewall with NAT deployed?

Which interface in the Cisco Unified Contact Center Enterprise solution is supported over a firewall with NAT deployed?

A.
Cisco Unified Contact Center Enterprise CTI OS Desktop and CTI OS for silent monitoring

B.
DMP between the Peripheral Gateway and Cisco Unified Contact Center Enterprise Call Routers

C.
Cisco TAPI QBE between the Peripheral Gateway and Cisco Unified Communications Manager cluster

D.
MDS or private network path between Cisco Unified Contact Center Enterprise Call Router pair (side A and side B)