What does a solid white line on the road signify?

A solid white line on the road signifies that drivers should not change lanes. This type of line is used to indicate that the lane you are in is meant to be maintained, and crossing over that line can lead to dangerous situations, especially in areas where lane changes might create a conflict with other vehicles or pedestrians.

While option A might suggest to change lanes with caution, the presence of a solid white line specifically prohibits that action for safety reasons. Similarly, a pedestrian crossing would typically be marked with a different kind of designation, such as a solid white line but with accompanying signage indicating the crosswalk. Option D, indicating road construction, is not applicable as construction zones are usually marked with cones, warning signs, or different line markings rather than a solid white line. Therefore, understanding the meaning of solid white lines is crucial for maintaining safety on the road.