Which reason for this behavior is ture?

You are configuring an L3Out interface for a VRF for which OSPF is configured on an ACI fabric. You notice that the OSPF routing table is rebuilt every 10 seconds.

Which reason for this behavior is ture?
A . OSPF timers are set to rebuild the RIB every 10 seconds
B . The loopback interfaces of the L3Out are configured with an IP addresses that is aleady in use
C . Aduplex mismatch is on the link on which L3Out is configured
D . This is the normal behavior of the ACI fabric

Answer: B