How is a taxiway defined in an airport?

A taxiway is specifically defined as a paved area designated for the movement of aircraft to and from runways and parking areas. It serves as the essential route that allows airplanes to travel safely and efficiently on the airport grounds without being on the active runway. This infrastructure is crucial for ensuring that air traffic flow is well-coordinated and that aircraft can reach their respective takeoff and landing areas without unnecessary delays or safety hazards.

In contrast, parking areas for passengers, unpaved routes between terminals, and secured areas for baggage handling do not accurately represent the function and purpose of a taxiway. Each of those options pertains to specific operational roles within an airport that are distinct from the critical function performed by taxiways. The correct option highlights the operational importance of taxiways in facilitating the smooth and safe transition of aircraft on the runway system.