Which option most closely describes how Barge functions?

Which option most closely describes how Barge functions?

A.
A supervisor listens in on a call on the same WAN or LAN with or without notification.

B.
A supervisor takes over a call with or without notification and terminates the party that is on the same network.

C.
A supervisor conferences in on a call on the same WAN or LAN with or without notification.

D.
A supervisor listens in on a call without notification and terminates the party that is on the same network.