In which two situations would a voice gateway be required? (Choose two.)

A.
To connect a corporate or branch location to an IP WAN

B.
To connect a corporate or branch location using VoIP to the PSTN

C.
To connect a Cisco Unified Communications Manager to a LAN

D.
To connect a Cisco Unified Communications network to a PBX

E.
To connect a corporate or branch location to a MAN