Which of the following factors affects a vehicle's reflectivity?

The shape of a vehicle plays a significant role in its reflectivity because it determines how light interacts with the vehicle's surfaces. A well-designed vehicle shape can enhance the effectiveness of reflective materials used in its construction, allowing light to bounce off more efficiently and improve visibility. The angles and contours of the vehicle influence the way it reflects light from headlights or other sources, which directly affects its overall visibility at night or in low-light conditions.

While other factors, such as the time of day, weather conditions, and speed of the vehicle, can influence how we perceive a vehicle or its reflective qualities, they do not have a direct impact on the physical properties of the vehicle's reflectivity itself. For example, in bright daylight, the effect of reflectivity might be less noticeable, but that doesn't change the inherent reflectivity based on shape. Similarly, weather conditions can alter visibility or the appearance of reflectivity, but the underlying factor of shape remains a key component in determining how the vehicle reflects light.