What are HOV lines indicated by?

Answer: B — White diamonds

HOV lines are indicated by white diamonds on the roadway. These symbols designate lanes that are reserved for high-occupancy vehicles, typically those carrying multiple passengers. The use of white diamonds clearly communicates to drivers that these lanes are intended for vehicles with a higher number of occupants, helping to promote carpooling and reduce traffic congestion. While other symbols, such as yellow, blue, or red, may be used for various purposes on the road, they do not serve the same function as the white diamond marking for HOV lanes. Understanding the significance of these markings is crucial for safe and compliant driving in areas where HOV regulations are enforced.