What signifies the end of a no-passing zone?

Answer: B — A solid yellow line

A no-passing zone is indicated by a solid yellow line. This type of marking is used to inform drivers that crossing the line to overtake another vehicle is not permitted due to potential hazards, such as curves or hills that limit visibility. The solid yellow line signifies that the section of road ahead is not safe for passing and encourages drivers to remain in their lane. In contrast, a solid blue line is typically used to indicate designated parking areas or special lanes, such as for handicapped parking, and does not relate to passing zones at all. A dashed yellow line indicates areas where passing is allowed, signaling that it is safe to overtake slow-moving vehicles under appropriate conditions. Traffic signs may provide additional instructions regarding passing zones, but they do not denote their beginning or end like the solid yellow line does. Thus, the solid yellow line is the recognized standard for marking the conclusion of a no-passing zone.