When are headlights required?

The requirement for using headlights is comprehensive and reflects various conditions that may affect visibility while driving. Headlights must be used half an hour after sunset until half an hour before sunrise, as this period typically experiences lower light levels, making visibility more challenging.

Additionally, headlights are necessary when there is insufficient natural light; this includes conditions like overcast days, heavy rain, or fog, where visibility is compromised regardless of the time of day. Finally, using headlights is also mandated whenever persons or vehicles cannot be seen from 1,000 feet, ensuring that drivers can spot pedestrians, cyclists, and other vehicles well in advance, which enhances safety on the road.

Therefore, recognizing that all these circumstances warrant the use of headlights emphasizes the importance of proper visibility to ensure safe driving. Hence, the requirement encompasses all these conditions, making the most comprehensive choice the correct answer.