Which two statements are true about VPN Monitor on a ScreenOS device? (Choose two.)
A. With a route-based VPN failure, VPN Monitor marks the tunnel interface status as down.
B. With a policy-based VPN failure, VPN Monitor marks the tunnel interface status as down.
C. VPN Monitor uses UDP to detect a VPN connection failure.
D. VPN Monitor uses ICMP to detect a VPN connection failure.