What best describes a traffic signal cycle length?

A traffic signal cycle length is best described as the time required for a complete sequence of signal indications. This encompasses the entire process of the traffic light changing through its various phases, including green, yellow, and red lights, before returning to the starting point. Understanding the complete cycle is important for traffic management, as it influences traffic flow, safety, and efficiency at intersections.

The other definitions provided do not fully capture the concept of cycle length. The duration of green signals only focuses on one part of the cycle, ignoring the transition to yellow and red phases. The time from the start of a red signal to the start of the next green signal describes a segment of the cycle rather than the cycle in its entirety. Lastly, the interval between the activation and deactivation of a signal can vary based on context and does not accurately reflect the continuous nature of a complete traffic signal cycle. Thus, the best choice is the one that encapsulates the whole sequence.