Tom works as a network administrator for the P4S company. The primary adaptive security
appliance in an active/standby failover configuration failed, so the secondary adaptive security
appliance was automatically activated. Tom then fixed the problem. Now he would like to restore
the primary to active status. Which one of the following commands can reactivate the primary
adaptive security appliance and restore it to active status while issued on the primary adaptive
security appliance?

A.
failover exec standby

B.
failover reset

C.
failover primary active

D.
failover active