What headlight rule applies in fog?

• A. Use high beams to maximize visibility
• B. In fog, use low beams
• C. Use only parking lights
• D. Turn on hazard lights instead of headlights

Answer: (B)

Fog scatters light, so using high beams in fog just creates more glare as the light bounces back from the droplets. Low beams aim light toward the road near the pavement, reducing that backscatter and helping you see the road surface, lane markings, and edges without blinding yourself. If your car has front fog lights, they can help in heavy fog when used with low beams, but they’re not a replacement for headlights. Hazard lights are for signaling a problem or warning other drivers, not for lighting the road. Parking lights are too dim for driving in fog. So, the best practice is to switch to low beams in fog.