What does a yellow traffic light indicate?

A yellow traffic light serves as a warning that the light is about to change to red. It indicates to drivers that they should prepare to stop if it is safe to do so. The purpose of the yellow light is to give approaching drivers sufficient time to react and either slow down or proceed with caution, depending on their distance from the intersection and their speed at that moment.

When a yellow light appears, it signifies that the right of way is changing, and drivers should be mindful of pedestrians and other vehicles that may also be adjusting their actions in response to the light change.

In this case, since the light is not malfunctioning, it is actively signaling a change in the traffic signal phase, contrasting with options that suggest the light is about to turn green, is malfunctioning, or is flashing, which denote different conditions not associated with the standard yellow traffic signal.