Which three statements about Cisco Discovery Protocol operations on a Cisco ME3400 switch are true?

A.	Cisco Discovery Protocol is enabled by default on NNI ports.
B.	Cisco Discovery Protocol is enabled by default on all NNI, ENI, and UNI ports.
C.	Cisco Discovery Protocol is disabled by default on ENI ports.
D.	Cisco Discovery Protocol is not supported on NNI or ENI ports.
E.	Cisco Discovery Protocol is not supported on UNI ports.