Which function does BFCP provide?

A.	BFCP is a secondary video channel that is used for content such as slide presentations and desktop sharing.
B.	BFCP is used to determine who is allowed to send media to the content channel
C.	BFCP provides the ability to pan, tilt, and zoom the far end's camera.
D.	BFCP negotiates who can send DTMF tones and when the tones are sent.