What is the most important factor for driving defensively at night?

The most important factor for driving defensively at night is using headlights effectively. This is crucial because visibility is significantly reduced during nighttime hours, and headlights play a vital role in illuminating the road, allowing drivers to see potential hazards and obstacles in their path. Proper use of headlights not only ensures that you can see well but also helps other drivers see you, reducing the chances of collisions.

While maintaining space around your rig is a good defensive driving practice at any time, including at night, it is secondary to the primary need for adequate visibility. When driving at night, managing the distance between your vehicle and others is important, but if visibility is impaired, it becomes challenging to gauge that distance effectively.

The options related to speed and turn signals address different aspects of driving safety. However, they do not directly tackle the essential need for visibility, which is the cornerstone of safe driving during nighttime. Thus, the effective use of headlights is the pivotal factor in ensuring safety while driving defensively at night.