If you need strong protection for the encryption of user data, what option would be the BEST choice?

If you need strong protection for the encryption of user data, what option would be the BEST choice?
A . When you need strong encryption, IPSec is not the best choice. SSL VPN’s are a better choice.
B . Use Daffier-Hellman for key construction and pre-shared keys for Quick Mode. Choose SHA in Quick Mode and encrypt with AE
C . Use AH protocol. Switch to Aggressive Mode.
D . Disable Differ-Hellman by using stronger certificate based key-derivation. Use AES-256 bit on all encrypted channels and add PFS to Quick Mode. Use double encryption by implementing AH and ESP as protocols.
E . Use certificates for Phase 1, SHA for all hashes, AES for all encryption and PFS, and use ESP protocol.

Answer: D