Which IPsec transform set provides the strongest protection?

Which IPsec transform set provides the strongest protection?

A.
crypto ipsec transform-set 1 esp-3des esp-sha-hmac

B.
crypto ipsec transform-set 2 esp-3des esp-md5-hmac

C.
crypto ipsec transform-set 3 esp-aes 256 esp-sha-hmac

D.
crypto ipsec transform-set 4 esp-aes esp-md5-hmac

E.
crypto ipsec transform-set 5 esp-des esp-sha-hmac

F.
crypto ipsec transform-set 6 esp-des esp-md5-hmac

Explanation: