In which two circumstances is Diameter Peer Discovery needed? (Choose two.)

A.
The Diameter client is rejected by the peer.

B.
The Diameter client must contact a first-hop Diameter agent.

C.
The Diameter agent must reply to the connect request of a Diameter client.

D.
The Diameter agent must search the next agent so that Diameter messages can reach
the Diameter server.

E.
The Diameter agent must close the session with a Diameter client.