Which type of vehicles is granted access on the airfield for hire purposes?

The correct answer identifies taxicabs and limousines as the types of vehicles granted access on the airfield for hire purposes because these vehicles are specifically designated for transporting passengers to and from the airport. Taxicabs and limousines operate as part of an established transportation network that provides services to travelers arriving and departing from airports. Access for these vehicles is typically regulated to ensure safety and efficiency in passenger transport, making them a necessary and recognized part of the airport's ground transportation system.

In contrast, personal vehicles are typically not allowed on the airfield due to security and safety concerns. Company-owned vehicles would mostly require specific permissions or permits to access certain parts of the airfield, but they are generally not used for hire. Rental cars, while they may be available on the airport's premises, don't access the airfield in the same manner and are usually not used for immediate passenger pick-up or drop-off on the runway area, further distinguishing them from the hired taxicabs and limousines.