Which of the following areas is restricted to authorized vehicles only?

Runways and taxilanes are critical areas within an airport's operations that are strictly reserved for authorized vehicles only. This restriction is in place due to the safety and security protocols necessary for aviation environments. These areas are where aircraft move on the ground, and only specific, properly authorized vehicles, such as airport staff vehicles, emergency services, and maintenance support vehicles, are allowed access. The presence of unauthorized vehicles in these areas could pose serious safety risks, including potential collisions with aircraft or disruptions to aircraft operations.

In contrast, passenger drop-off zones, parking lots, and public waiting areas typically allow for public access. Passenger drop-off zones are designed for immediate and brief stopping to let passengers disembark, while parking lots offer spaces for vehicles to remain parked for longer durations. Public waiting areas are accessible to travelers and their friends or family waiting for flights. Hence, these locations do not have the same restrictions as runways and taxilanes, which prioritize operational integrity and safety.