What does a yellow hold short line indicate?

Answer: B — The driver must stop before crossing the line

A yellow hold short line is a critical visual indicator on airfields that signifies where vehicles must stop to ensure safety and compliance with air traffic operations. When a driver sees this line, it indicates that they must come to a complete stop before crossing it. This requirement is in place to prevent vehicles from inadvertently entering active runways or taxiways where aircraft are operating, thereby reducing the risk of accidents. Understanding the purpose of the yellow hold short line is essential for maintaining safety protocols on an airfield. It is designed to help drivers clearly identify the boundary they must respect to avoid incursions into areas where aircraft may be taking off or landing. Thus, the indication to stop before crossing ensures that ground movement remains coordinated and secure.