Final answer:
You must switch your vehicle's headlights to low beams when approaching or overtaking another vehicle within 500 feet for safety reasons.
Step-by-step explanation:
The correct answer is: 4) 500 feet. When driving a vehicle, it is important for safety to switch your headlights to low beams when approaching or overtaking another vehicle within 500 feet. This is to ensure the driver of the other vehicle is not blinded by your headlights, which could potentially lead to an accident. Following this rule helps maintain safe driving conditions for all vehicles on the road.