A broken white line on the road represents:

A broken white line on the road is used to indicate lanes of traffic moving in the same direction. This type of line allows vehicles to change lanes when it is safe to do so. The presence of a broken line signifies that the lane change is permissible, as long as it can be done safely without interfering with other vehicles.

In contrast, a solid white line would indicate that lane changes are discouraged or prohibited. Understanding the meaning of lane markings is crucial for safe driving practices, as it helps to maintain smooth traffic flow and ensures that drivers make informed decisions on when to change lanes. The other options do not represent the function of a broken white line, as they refer to different road markings or conditions that are unrelated to lane designation.