When must headlights be on according to Delaware regulations?

Answer: C — When visibility is low

Headlights must be on whenever visibility is low, as this ensures that drivers can see clearly and are visible to others on the road. In Delaware, this includes conditions such as during rain, fog, or snow, as well as at dusk and dawn when light levels may be insufficient. It's critical for safety that vehicles are equipped with functioning headlights in these situations to help prevent accidents and improve overall visibility. In contrast, headlights are not required to be on during daylight hours unless specified by special conditions, and while they are essential at night, the regulations emphasize their use in low visibility situations to enhance safety rather than only focusing on the time of day. Thus, having headlights activated whenever visibility is compromised is a key aspect of responsible driving.