Which of the following best describes baggage tugs?

Baggage tugs are specifically designed for the transfer of luggage between the aircraft and the terminal or baggage handling areas. Their primary function is to facilitate the efficient movement of baggage, ensuring that it is safely transported and loaded or unloaded as needed. This unique purpose differentiates them from other vehicle types, making them integral to the airside operations.

The other options do not accurately reflect the role of baggage tugs. Passenger transport vehicles are meant for carrying passengers rather than luggage. Emotional support vehicles, while they may provide comfort, do not relate to the logistics of baggage handling at airports. Maintenance vehicles on the tarmac are designed for repair and upkeep of airport infrastructure and are not involved in the handling of luggage. Thus, recognizing baggage tugs as specialized airside vehicles for luggage transfer accurately captures their essential function in airport operations.