Which statement about scalability in Cisco OTV is true?

A.
Unknown unicasts are handled by the authoritative edge device.

B.
The control plane avoids flooding by exchanging MAC reachability.

C.
Any encapsulation overhead is avoided by using IS-IS.

D.
IP-based functionality provides Layer 3 extension over any transport.

Explanation:

http://www.cisco.com/en/US/docs/solutions/Enterprise/Data_Center/DCI/whitepaper/DCI_1.html#
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