What switch must be turned on to energize the missile warning system?

The switch that must be turned on to energize the missile warning system is the Power switch. This is critical because the missile warning system requires power to operate effectively. Once the Power switch is activated, it enables the system to begin monitoring for potential missile threats. Without this switch being in the 'on' position, the necessary electronics and sensors would not function, rendering the missile warning system inactive.

While other switches may play roles in various functions like managing specific alerts or providing audio cues, they do not initiate the system's basic operational capability, which is fundamentally tied to the availability of power. Thus, understanding the necessity of the Power switch ensures that pilots are prepared to properly activate essential safety systems during flight.