Which of the following is a legal requirement for driving in foggy conditions?

Using low beam headlights in foggy conditions is a legal requirement because they provide better visibility without causing glare that can reflect off the fog. High beam headlights illuminate further ahead but can create a blinding effect when their light is scattered by fog, rain, or snow, reducing overall visibility. It's essential in foggy situations to use low beam headlights, as they are designed to shine downward and illuminate the road directly in front of the vehicle, enhancing safety for the driver and other road users.

Turning off all headlights is unsafe, as it completely eliminates visibility, making it difficult to see the road and for other drivers to see you. Driving with parking lights only does not provide adequate illumination for navigating fog, as parking lights are primarily meant for visibility when a vehicle is parked. Therefore, using low beam headlights is both a legal requirement and a best practice for driving safely in foggy conditions.