JAVA/Sun Exam Questions

Which item in the list would be specifically required for a VPN compared to a mode without encryptio

Which item in the list would be specifically required for a VPN compared to a mode without encryption?

A.
Authentication Header (AH)

B.
Internet Key Exchange (IKE)

C.
Encapsulating Security Payload (ESP)

D.
Streams Control Transmission Protocol (SCTP)