Final answer:
During rain, snow, or fog in the daytime, drivers should switch on their low-beam headlights for better visibility and to remain conspicuous without causing glare to others.
Step-by-step explanation:
When it is raining, snowing, or foggy during the day, a driver should turn on the low-beam headlights. This enhances visibility and ensures other drivers can see your vehicle. The low-beam setting is essential because it provides sufficient illumination without causing significant glare to other drivers, which can be particularly dangerous in poor visibility conditions. High-beam headlights can reflect off precipitation or fog, worsening visibility for all road users. Headlights not only allow you to see better but also make you more visible to others. It's important to avoid looking directly at bright lights to protect your eyes.