Which feature is required for graceful restart to recover from a processor failure?

Which feature is required for graceful restart to recover from a processor failure?
A . Cisco Express Forwarding
B . Virtual Switch System
C . Stateful Switchover
D . Bidirectional Forwarding Detection

Answer: C

Explanation:

https://archive.nanog.org/meetings/nanog42/presentations/Weissner_SSO.pdf

The Stateful Switchover (SSO) feature works with Nonstop Forwarding (NSF) in Cisco software to minimize the amount of time a network is unavailable to its users following a switchover. The primary objective of SSO is to improve the availability of networks constructed with Cisco routers.