What improvement does EAP-FASTv2 provide over EAP-FAST?

What improvement does EAP-FASTv2 provide over EAP-FAST?

A.
It allows multiple credentials to be passed in a single EAP exchange.

B.
It supports more secure encryption protocols.

C.
It allows faster authentication by using fewer packets.

D.
It addresses security vulnerabilities found in the original protocol.