When must headlights be used in Montana?

Using headlights in Montana is required from sunset to sunrise to enhance visibility during nighttime driving. Additionally, headlights must be engaged during adverse weather conditions, such as rain, snow, fog, or any situation where visibility is substantially limited. This requirement aims to ensure that drivers can see the road clearly and that their vehicle can be seen by others, which is crucial for maintaining safety on the roads.

In contrast, limiting headlight use to only nighttime driving would not account for conditions like fog or heavy rain during the day. Similarly, using headlights exclusively in fog would miss other essential situations for their use, such as nighttime driving or driving in heavy rain. Finally, requiring headlights at all times during the day is unnecessary since there are conditions where visibility is adequate without them, except in specific weather scenarios that impair sight. Consequently, the correct answer encompasses a comprehensive understanding of when headlights should be used to promote safety under varying light and weather conditions.