What do solid white lines on the road indicate?

Solid white lines on the road signify that no lane changes are allowed. This is an important safety measure, as these lines typically delineate lanes that should not be crossed under normal driving conditions, especially when the road is busy or in areas where changing lanes could pose a risk to vehicles or pedestrians. Drivers should remain within their designated lanes marked by solid white lines to maintain traffic flow and safety.

The other options relate to different road markings or traffic rules. For instance, lane changes being permitted would typically be signified by dashed lines, and while solid white lines can indicate that traffic is moving in the same direction, the critical point here is about the lane change restriction. Additionally, pedestrian crossings are usually marked by different symbols or types of lines rather than solid white lines. Therefore, interpreting solid white lines correctly is essential for safe driving practices.