Final answer:
A police officer can overrule a traffic signal to manage traffic and ensure safety. Neither pedestrians, cyclists, nor motorists have such authority. Officers take precedence over automated signals during emergencies or to prevent accidents.
Step-by-step explanation:
The individual who has the authority to overrule a traffic signal is a police officer. In cases where safety is at risk or an unusual situation occurs, a police officer can direct traffic in a manner that overrides standard traffic control devices. This could include directing vehicles to move through a red light or stop despite a green light. Neither pedestrians, cyclists, nor motorists have the authority to disregard traffic signals as they are required to follow the rules of the road to ensure safety for all. A common example of a police officer's right to control traffic would include situations where there may be hazards at an intersection or when a pedestrian's safety, such as students crossing to campus, is a concern. An officer's presence and signals take precedence over automated traffic lights.