What must vehicles do when approaching a hold position marking from the dashed-line side?

When approaching a hold position marking from the dashed-line side, vehicles are required to get approval to continue moving. This is essential for maintaining safety within the airport environment, as hold position markings are designated areas where vehicles must stop to avoid interfering with aircraft operations.

The purpose of requiring approval before proceeding is to ensure that the vehicle driver receives clear communication from air traffic control or ground control, confirming that it is safe to continue. This practice helps prevent collisions or accidents on the airfield, which could pose significant risks to both vehicles and aircraft.

In contrast, other options suggest actions that could compromise safety or lead to a lack of necessary communication with air traffic personnel. For instance, simply continuing without stopping could lead to dangerous situations if an aircraft is approaching. Turning around or switching to an alternate route would generally not be appropriate responses in this context either, as they could disrupt the flow of operations or create confusion on the airfield. Thus, seeking clearance aligns with standard operating procedures designed to prioritize safety and coordination on the airport premises.