Which auxiliary power unit serves as an external power source for the MQ-1 and MQ-9 aircraft?

The option that serves as an external power source for the MQ-1 and MQ-9 aircraft is the starter cart assembly (SCA). The SCA is designed to provide the necessary electrical power to start the aircraft engines and support onboard systems when the aircraft is on the ground and not running.

When the engines are not operating, the internal batteries cannot supply the required voltage and amperage for all systems, making the SCA essential for pre-flight checks and initial start-up. This external support ensures that critical systems powering avionics and other functions are operational prior to flight.

In contrast, while other options may contribute to aircraft operations in different contexts, they do not specifically provide the external electrical power needed during ground operations like the SCA does. The DC generator and AC inverter serve different roles in the electrical system of the aircraft during flight, generating power rather than supplying external support before engine start. The A/M 32A-95 is more of a maintenance tool than a direct power source for initiation. Thus, the SCA's specific role makes it the correct choice for this question.