In which of the following situations is stopping required?

Stopping is required at a stop sign because the purpose of a stop sign is to indicate that drivers must come to a complete halt at the intersection. This allows for safe evaluation of the intersection for any oncoming traffic or pedestrians before proceeding. The law mandates this behavior to ensure that all road users can safely navigate through intersections where visibility may be limited or where traffic may be present from different directions.

In contrast, other scenarios such as when the light is green, going through a roundabout, or when the road is clear do not necessitate a complete stop. A green light indicates that it is safe to proceed, while roundabouts typically require yielding to traffic already in the roundabout rather than a complete stop. Furthermore, if the road is clear, there’s no need to stop unless specific traffic controls like a stop sign are present.