When must you dip your lights?

Dipping your lights is essential for ensuring safe driving, particularly in conditions that can blind or distract other drivers. The requirement to dip your lights applies when approaching oncoming vehicles because high-beam headlights can create a glare that impairs the vision of drivers coming in the opposite direction. This is crucial for preventing accidents and maintaining visibility for everyone on the road. Additionally, in situations like wet roads at night, proper lighting is vital for safe navigation, as it helps illuminate potential hazards without causing distraction to others.

In contrast, while following another vehicle closely can require adjusting your lights to avoid dazzling the driver ahead, the primary focus of dipping lights is on oncoming traffic and certain road conditions. Dipping lights on highways isn't universally required unless there's oncoming traffic. Lastly, using lights at all times at night isn't necessary; there are circumstances, such as well-lit roads, where full beam may be appropriate without endangering others. Therefore, option B most accurately encompasses the rules surrounding when to dip headlights for the safety of all road users.