Which statement would explain why the overlay interface on an OTV edge device is not in the up state?
A. The site identifiers are identical within a multihomed site.
B. Multicast groups are not mapped to a range of SSM addresses to carry the multicast traffic.
C. An adjacency server is not configured for connectivity over a multicast transport.
D. The OTV IS-IS metrics do not match across all adjacent OTV edge devices.
