Final answer:
In fog, snow, or heavy rain, use low beams to improve visibility and road safety by reducing glare from light scatter.
Step-by-step explanation:
When driving in fog, snow, or during heavy rain, it is crucial to use the low beams of your vehicle's headlights. High beams can cause light to scatter more in these weather conditions, leading to worse visibility because the water droplets or snowflakes in the air act like tiny prisms. By using low beams, the light is directed closer to the road and reduces the glare caused by the reflection and scattering of light, making it safer for driving.