Can the APU be used to heat the aircraft during anti-ice application?

The correct choice indicates that the APU (Auxiliary Power Unit) cannot be used to heat the aircraft during anti-ice application. This is essential because the APU's primary function is to provide electrical power and bleed air for various systems while the aircraft is on the ground and during operations that do not require the engines to be running.

In most cases, the appropriate method for anti-ice application involves using the engines for bleed air to ensure that the systems operate effectively. This is particularly important in maintaining proper temperatures in critical areas of the aircraft, such as the wings and engine inlets, to prevent ice accumulation.

Additionally, using the APU for heating during anti-ice may not provide the necessary airflow or temperature control as efficiently as the engine bleed air systems would, potentially compromising the effectiveness of the anti-ice measures. Therefore, while the APU has several auxiliary capabilities, its use in this specific context is not standard practice.