Which of the following actions is not safe when driving in foggy conditions?

Using high beam headlights in foggy conditions is not safe because the light from high beams tends to reflect off the fog, causing glare that can severely reduce visibility. Fog is composed of tiny water droplets that scatter light, and when high beams are used, this scattering effect can create a wall of light that obscures your view of the road ahead.

In contrast, low beam headlights are designed to shine more directly onto the road and can help illuminate the area immediately in front of your vehicle without creating excessive glare. Reducing speed and increasing following distance are both critical actions to take in fog, as they allow for greater reaction time to potential hazards that may be obscured by low visibility. These strategies help ensure that you can navigate safely in such challenging conditions.