Which description of the function of a Cisco APIC is true?

A.	The APIC discovers only the leaf switch to which it directly connects
B.	The APIC exposes a north bound API by using XML and JSON.
C.	The infrastructure VLAND ID of the ACI fabric is used to communicate between the controller and the VMware vCenter server.
D.	When communication to the APIC is down, the Cisco ACI fabric fails to forward traffic.