In conditions of thick fog, you must...

In conditions of thick fog, you must...
A)drive with only the front fog light on.
B)drive on the hard shoulder.
C)reduce speed.Correct
Fog suddenly reduces visibility, and in some cases even makes it impossible to continue driving. When driving in fog, we must reduce speed to adapt it to our field of vision.
We must use the vehicle's lights. When the fog is thick, in addition to the dipped headlights, we must mandatorily use the rear fog light and the front fog light if we have one (its installation is optional).