For which reason can OSPFv3 fail to start between two routers?
A . OSPFV3 is configured only under an interface
B . The interface assigned to OSPFv3 is in NBMA mode with only one neighbor defined
C . The router is configured with IPv6 addresses only and it is unable to find an OSPFv3 router ID
D . IPV6 unicast routing is enabled
Answer: C