When should a driver use their hazard lights?

Using hazard lights is intended to alert other drivers that there is a situation requiring caution, typically when a vehicle is unable to proceed safely or is stopped for an unexpected reason. In the case of an emergency, such as a breakdown or another situation that poses a risk on the roadway, activating hazard lights signals to other vehicles that they should be cautious and prepared for possible obstacles or unusual behavior on the roadway.

While there are times when a driver might consider using hazard lights—like when experiencing heavy rain or during nighttime driving—the primary purpose of these lights is to indicate a vehicle is stationary due to an issue, thus making option C the most appropriate and correct choice. It effectively communicates to approaching drivers that they should exercise additional care because the vehicle represents a potential hazard.

The other scenarios mentioned—changing lanes, driving in the rain, or at night—do not typically require the use of hazard lights and are governed by standard driving practices that focus on signaling maneuvers and maintaining visibility without highlighting specific hazards.