Which of the following two statements about Cisco NSF and SSO are the most relevant to thenetwork designer？ （）
A、 You can reduce outage 1 to 3 seconds by using SSO in Layer 2 environment or Cisco NSF with SSO in a Layer 3 environment.
B、 SSO and NSF each require the device to either be graceful restart-capable or graceful-aware.
C、 In a fully redundant topology adding redundant supervisor a with NSF and SSO may causelonger convergence times than single supervisors with turned IGP times
D、 The primary deployment scenario for Cisco NSF with SSO is in the Distribution and Corelayers.
E、 Cisco NSF-aware neighbor relationship are independent of any turned IGP times
