What is the primary function of a traffic signal?

Answer: B — To control vehicle and pedestrian traffic at intersections

The primary function of a traffic signal is to control vehicle and pedestrian traffic at intersections. Traffic signals are essential for managing the flow of traffic and ensuring safety for all road users. When traffic signals operate correctly, they provide clear instructions to drivers and pedestrians about when to stop and when to go, thereby minimizing the risk of accidents. These signals use different colors—typically red, yellow, and green—to convey specific actions. A red light indicates that vehicles must stop, a green light allows traffic to proceed, and a yellow light warns of an impending stop. This system is critical in busy intersections where multiple roads converge and where the potential for conflict between vehicles and pedestrians is significant. By effectively managing the timing of these lights, traffic signals support orderly traffic movement, reduce congestion, and contribute to overall road safety, emphasizing why their primary role is traffic control rather than marking road ends, indicating speed limits, or providing directions.