South Carolina Driver's Permit Practice Exam

When driving in fog, snow, or rain, which headlights must be used?

1. high-beam

2. low-beam

3. hazard lights

4. daytime running lights

The correct answer is: low-beam

When driving in fog, snow, or rain, low-beam headlights must be used. This is because low beams provide better illumination of the road directly in front of your vehicle without causing excessive glare that can reflect off the precipitation in the air. High beams can create a "whiteout" effect in these conditions, as the light reflects off the fog, snow, or rain, making it difficult to see. Using low beams allows for improved visibility and safety, as it lights up the road while minimizing the glare that can impair both your vision and the vision of other drivers. Hazard lights serve a different purpose and are used to indicate a vehicle's presence or alert other drivers in specific situations, rather than for visibility enhancement while driving. Daytime running lights are designed to make your vehicle more visible to others during the day, but they do not provide adequate illumination of the road in low visibility conditions.