What should you do when driving in fog?

Answer: B — Use low beam headlights

When driving in fog, using low beam headlights is the most effective option. Low beam headlights are designed to illuminate the road immediately in front of your vehicle without causing glare that can reflect off the fog and impair your visibility further. This helps ensure that you can see and be seen by other drivers. High beam headlights, on the other hand, can create a blinding effect when they hit the fog, causing a dangerous situation where you cannot see ahead clearly. Driving without any headlights can severely limit your visibility, making it difficult for you to see the road as well as for other drivers to see you. Relying solely on hazard lights is also not a suitable option for navigation; they are intended to signal others that you are stationary or experiencing an emergency, not for illumination. Thus, low beam headlights provide the best combination of visibility for both the driver and others on the road in foggy conditions.