When driving in fog, you should use

Explanation

Turn on your low-beam headlights whenever visibility is reduced, such as in bad weather. (In fog, fog lights are an alternative.) Don't use high-beam headlights in bad weather. The bright lights can reflect off fog, rain, or snow and cause glare. However, if fog becomes so dense that you cannot see even 10 seconds ahead, pull off the road and stop in a safe place. Remember: If you can't see, you can't drive.