When must headlights be turned on in Idaho?

Answer: D — From sunset to sunrise and during reduced visibility

In Idaho, headlights must be turned on from sunset to sunrise and during reduced visibility conditions. This requirement is crucial for ensuring safety on the roads. During nighttime, headlights illuminate the area ahead, making it easier to see other vehicles, pedestrians, and road signs. Additionally, when visibility is reduced due to weather conditions such as rain, fog, or snow, headlights help other drivers see your vehicle, reducing the risk of accidents. Proper use of headlights enhances situational awareness for all road users. It is not just about the time of day; the emphasis on reduced visibility underscores the importance of being proactive about safety whenever conditions are less than ideal. The other answer choices either provide incomplete information or focus only on specific times or situations, which do not capture the broader requirements set by the law.