What would be the correct order of steps needed to perform this task?

Exhibit:
Chris has lost SIC communication with his Security Gateway and he needs to re-establish SIC.
What would be the correct order of steps needed to perform this task?

A.
5, 1, 2, 4
B. 5, 1, 4, 2

C.
3, 1, 4, 2

D.
2, 3, 1, 4