A companys network consists of a primary switch at one end of the office building and a secondary switch at the other end of the building, which are networked together. The office experiences a brownout only affecting the half of the building connected to the secondary switch.
When power is restored, users connected to the secondary switch report no network or Internet connectivity. Which of the following should be verified on the secondary switch to resolve this issue?

A.
Verify VLAN assignment

B.
Verify there is not a duplicate IP address

C.
Verify subnet mask

D.
Verify the switch has power