Which statements best describe auto discovery VPN (ADVPN). (Choose two.)

Which statements best describe auto discovery VPN (ADVPN). (Choose two.)
A . It requires the use of dynamic routing protocols so that spokes can learn the routes to other spokes.
B . ADVPN is only supported with IKEv2.
C . Tunnels are negotiated dynamically between spokes.
D . Every spoke requires a static tunnel to be configured to other spokes so that phase 1 and phase 2 proposals are defined in advance.

Answer: A C