Which statement best describes a green interval in a traffic signal?

A green interval in a traffic signal specifically refers to the time during which vehicles can pass through the intersection without stopping. This period allows traffic to flow freely and is critical for efficient movement at intersections, especially in areas with heavy vehicle activity.

Understanding the green interval helps in managing traffic flow and minimizing delays for drivers. It is the time highlighted on signal timing plans to facilitate smooth vehicle movement, directly affecting the overall efficiency of the intersection's traffic management.

The other options do not capture the specific meaning of a green interval. The entire cycle of traffic signal changes encompasses the whole process of red, yellow, and green phases but doesn't focus solely on the time vehicles are allowed to proceed. The duration of all signaling phases combined refers to the entire time the signal operates continuously, which is broader than just the green interval. Lastly, the period when all lights are red indicates a completely different state of a traffic signal, where vehicles are required to stop, contrasting sharply with the purpose of the green interval.