What do 'countdown markers' at motorway exits indicate?

Countdown markers at motorway exits serve as a wayfinding tool for drivers, indicating the distance remaining to the exit point. These markers typically display incremental distances, often shown in hundreds of meters, allowing drivers to anticipate their exit and prepare for any transitions needed, such as lane changes or speed adjustments. This information is crucial for safe and efficient driving, particularly in high-speed environments like motorways where timely decisions are essential.

The other options relate to different aspects of motorway driving, but they do not address the primary function of countdown markers specifically. For instance, distance to service areas or speed limit changes provides helpful information for drivers but does not pertain directly to the purpose of countdown markers. In this context, only the distance to the exit is accurately represented by these markers, making it the correct answer.