It is very foggy. You should slow down and:

1. Turn on your emergency flashers.
2. Turn your lights to their high beam setting.
3. Turn your lights to their low beam setting. ✓

Answer: C. Turn your lights to their low beam setting.

Slow down and turn your headlights to the low-beam setting.

Why this is the answer

The California handbook says that in heavy fog you should drive slowly and use your low-beam headlights. It explains that high beams reflect back off the fog and cause glare, which makes it harder to see. The handbook also says that if you need your windshield wipers because of fog, you must turn on your low-beam headlights. Emergency flashers are mentioned for when the fog is too thick and you pull off the road to wait.

Why the other answers are wrong

• A. Turn on your emergency flashers. — Emergency flashers are described for when you pull off the road because the fog is too thick to drive safely, not as the lighting choice while you keep driving slowly.
• B. Turn your lights to their high beam setting. — High beams reflect back from fog and cause glare, so the handbook tells you to use low beams instead.

Remember it

Think low beams for low visibility: fog sends high beams back at you.