From Your Core Site, Your Network Management System (NMS) Has

From your core site, your network management system (NMS) has detected that both the WAN router and the switch in one of your remote sites are unreachable. What should be your first step in identifying the root cause?

A) examine the state of the adjacent core router's interface
B) examine the switch configuration at the core site
C) examine the router configuration at the remote site
D) examine the state of the remote router's WAN interface