A traffic rotary is justified where A. number of intersecting roads is between 4 and 7 B. space is limited and costly C. when traffic volume is less than 500 vehicles per hour D. when traffic volume is more than 5000 vehicles per hour

The correct answer is: A. number of intersecting roads is between 4 and 7.

A traffic rotary is a type of intersection in which traffic flows in a circular pattern around a central island. They are often used in areas with high traffic volumes, as they can help to improve traffic flow and reduce congestion.

Traffic rotaries are typically justified when the number of intersecting roads is between 4 and 7. This is because rotaries are most efficient when there are a moderate number of roads converging at a single point. If there are too few roads, a rotary may not be necessary, as traffic can be easily managed with stop signs or traffic lights. If there are too many roads, a rotary may become too congested, and it may be more efficient to use a different type of intersection, such as a signalized intersection.

Options B and C are incorrect because rotaries can be used in areas with limited space or high traffic volumes. Option D is incorrect because rotaries are typically used in areas with moderate traffic volumes.