When must a driver use headlights under normal weather conditions?

Answer: B — half hour after sunset and a half hour before sunrise

Using headlights during a half hour after sunset and a half hour before sunrise is essential for ensuring visibility and safety on the road. This time frame is when daylight fades, and natural light diminishes significantly. By using headlights during these hours, drivers can see better and allow other road users to see them, reducing the risk of accidents. It's a legal requirement in many jurisdictions, including South Carolina, to enhance safety during these periods of low light. While it's important to use headlights in other situations, such as during periods of low visibility, rain, or fog, the specific rule regarding sunset and sunrise emphasizes the regular need to operate with headlights for both the safety of the driver and others on the road. Options that suggest headlights are needed only in specific conditions or situations, like rain or highway driving, would not provide adequate visibility in all necessary circumstances.