What does a solid yellow line on the road signify?

A solid yellow line on the road signifies that no passing is allowed. This marking is used to indicate that the road is considered hazardous for overtaking another vehicle. It serves as a visual warning to drivers that there may be potential dangers ahead, such as curves, intersections, or other conditions that require a driver to stay in their lane. The presence of a solid yellow line essentially communicates that safety is a priority, and drivers should remain cautious and not attempt to cross this line to pass another vehicle.

In contrast, the other options refer to different road markings or regulations. A solid yellow line does not indicate permissions for passing, nor does it denote bike lanes or the conclusion of school zones, which are marked differently to convey specific traffic rules. Understanding this marking is essential for road safety and compliance with traffic laws.