To configure 6to4 tunneling on a dual-stack edge router. Which three of the following are
valid components in 6to4 Tunneling configuration? (Choose Three)

A.
IPv4 Tunnel IP address

B.
Tunnel mode (6to4)

C.
Tunnel Keepalives

D.
IPv4 Tunnel Destination

E.
IPv4 Tunnel Source

F.
6to4 IPv6 address (within 2002::/16)

Explanation:
http://packetlife.net/blog/2010/mar/15/6to4-ipv6-tunneling/ (see 6to4
configuration, all three bullets)