What is a 'roundabout' in traffic rules?

Answer: B — circular intersection where you yield to traffic

A roundabout is defined as a circular intersection designed to improve traffic flow and safety. In a roundabout, vehicles entering the roundabout must yield to the traffic that is already circulating within it. This design minimizes the potential for head-on collisions and allows for a smoother transition through intersections, as it typically does not require traffic signals or stop signs. Yielding to traffic already within the roundabout ensures that vehicles can keep moving potentially without stopping, which helps reduce congestion and delays. This design encourages a continuous flow of vehicles, allowing for efficient movement in various directions and often resulting in shorter travel times compared to traditional intersections. Other options such as a rectangular intersection, a type of road sign, or a parking place do not accurately represent the function or characteristics of a roundabout, which is specifically focused on circular traffic management.