Whitfield Diffie and martin Hellman gave their names to what standard?

A.
An encryption scheme that makes pre-shared keys obsolete

B.
An algorithm that is used in IPsec QuickMode and as an additional option in IPsec QuickMode (PFS)

C.
A Key Exchange Protocol for the advanced Encryption Standard

D.
A Key Agreement / Derivation Protocol that constructs secure keys over an insecure channel.