Which statement describes OTV configuration on the Cisco Nexus 7000 Series Switches？ （）

• A、 The OTV control-plane protocol uses the IS-IS protocol to establish adjacencies and exchange MAC reachability across the overlay network. You must enable IS-IS with the feature isis command before OTV adjacencies can be established.
• B、 OTV uses an SSM group range for neighbor discovery and to exchange MAC reachability with other OTV edge peers.
• C、 The OTV join interface is a routed uplink interface on the edge device used to physically join the overlay network.
• D、 The OTV internal interface encapsulates the site Layer 2 frames in IP unicast or multicast packets that are then sent to the other sites.