You are the new Trainee. The lecturer asked that which of following statements is the grace period
in a graceful restart situation?

A.
how long the supervisor waits for Cisco Nonstop Forwarding replies

B.
how often graceful restart messages are sent after a switchover

C.
how long NSF-aware neighbors should wait after a graceful restart has started before tearing down adjacencies

D.
how long theNonstopForwarding-capable switch should wait after a graceful restart has started before tearing down adjacencies