What is the rule for using headlights in reduced visibility?

Using headlights when visibility is less than 500 feet is essential for safety. In conditions such as rain, fog, snow, or at night, visibility can be significantly reduced, making it harder to see other vehicles, pedestrians, or roadway markers. By turning on headlights in these situations, drivers enhance their visibility to others and allow themselves to see more clearly. This rule is a standard safety practice to prevent accidents and ensure everyone on the road can respond appropriately to changing conditions.

Other options suggest limited scenarios or incorrect practices. For instance, using headlights only in fog does not account for other circumstances that can impair visibility. Saying that headlights are optional if street lights are on undermines the need for additional visibility, especially on poorly lit roads. Finally, the notion of using high beams only in darkness ignores the fact that high beams can dazzle other drivers and should be used judiciously. Thus, using headlights in reduced visibility conditions aligns with good driving safety practices.