Lighting and Optical Signals
When is the use of the rear fog light mandatory?
Reviewed on 26 Jul 2026
- A On any night-time journey
- ✓ In dense fog, heavy rain, or snow
- C Whenever driving on a motorway
- D Only when parking at night
Why this is the correct answer
The rear fog light is mandatory in conditions of dense fog, heavy rain, or snow, as its high intensity allows the vehicle to be seen from behind. It must be switched off as soon as visibility improves to avoid dazzling.
More questions on Lighting and Optical Signals
- The front fog light is:
- After driving through a stretch of dense fog with the rear fog light on, visibility improves. What should you do?
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- In which of these situations must the hazard warning lights be used?
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