California DMV Permit Test (Class C)Safe Driving PracticesMedium
You are driving in heavy fog. Which of the following is the most appropriate use of your vehicle's lights?
- AParking lights only.
- BLow-beam headlights.
- CHigh-beam headlights.
- DDaytime running lights (DRLs) only.
Show answer & explanationAnswer & explanation
Correct answer: B. Low-beam headlights.
In heavy fog, high-beam headlights reflect off the fog particles and can actually reduce your visibility. Parking lights and DRLs are not bright enough to be effective. Low-beam headlights are designed to illuminate the road without causing excessive glare back at the driver, providing the best visibility in foggy conditions.
Why the other options are wrong
- A. Parking lights are not sufficient for driving in fog; they are for parked vehicles.
- C. High beams will reflect off the fog and worsen your visibility.
- D. DRLs are not designed for adverse weather conditions and are insufficient for fog.
Driving in Fog
When driving in fog, use low-beam headlights to maximize visibility and minimize glare.
- High beams are counterproductive in fog.
- Low beams direct light down and forward.
- Fog lights (if available) can also be used in conjunction with low beams.
Memory trick: Fog's a wall, high beams fall; low beams call.