A technician, Joe, visits a site that has reported a network down emergency. He immediately reboots the switches and the router since the network is down. Which of the following network troubleshooting methodology steps should Joe have performed FIRST?

A.
Determine if anything has changed

B.
Once a theory is confirmed determine the next step is to resolve the problem

C.
Implement the solution or escalate as necessary

D.
Question the obvious