You are driving in fog that has become too thick to see the road safely. What does the manual say to do?
-
A.
Switch on high beams and stay at the posted speed.
-
B.
Turn on hazards and follow the taillights of the vehicle ahead.
-
C.
Slow to about 5 to 10 mph and keep driving.
-
D.
Pull off the roadway and stop until conditions improve. Correct
The answer is "Pull off the roadway and stop until conditions improve."
The manual's answer in fog too dense to see through is to pull off the roadway and stop. Choice C is the pull, because slow-and-steady feels like sensible fog behavior; the manual specifically tells you not to creep at 5 to 10 mph, since drivers behind you cannot judge that speed in time to avoid you.
The traps in the wrong answers
A. Switch on high beams and stay at the posted speed.
High beams glare off fog droplets and worsen visibility; posted speed is too fast for the conditions. This answer imports a night-driving habit into fog, where more light thrown forward comes right back at the driver.
B. Turn on hazards and follow the taillights of the vehicle ahead.
The manual does not endorse chasing another driver's taillights in fog. This answer trusts the vehicle in front as a guide, turning any mistake that lead driver makes into a crash you share.
C. Slow to about 5 to 10 mph and keep driving.
The manual specifically says not to drive at 5-10 mph in fog. This answer reads a crawl as the safest speed, forgetting that a driver behind cannot judge a near-stopped vehicle in fog until it is too late.
This question tests your knowledge of Defensive Driving in Illinois. Source: Illinois Rules of the Road, "Chapter 11: Safe Driving Tips, Weather Conditions, Fog," p.84..
Related Illinois questions
- According to the manual, what is the cause of most rear-end crashes? →
- You are using the three-second rule to check your following distance. After the vehicle ahead passes a fixed object, your vehicle should not reach that object before which count? →
- What kind of reference point does the manual say to pick when using the three-second following-distance rule? →
- The road is wet and visibility is poor. How should you adjust your three-second following distance? →
- Another driver is tailgating you. What does the manual instruct you to do? →
You just took one Illinois question apart. The book does it for the whole test.
The Illinois book unlocks a free companion: an adaptive study plan, progress synced across your devices, a denser laminate cheat sheet, and a test-day walkthrough. Verify your copy once, usually in seconds; there's nothing extra to buy.
$18.99 paperback, free companion included.