Vision blocks occur when
- there are wet leaves or other debris on the road.
- a truck is in the next lane. ✓
- you are riding on a straight and clear road.
- All of the above
Answer: B. a truck is in the next lane.
A vision block happens when a large truck in the next lane blocks your view of what's ahead.
Why this is the answer
The handbook treats anything that keeps you from seeing the road ahead as a hazard, and it lists specific examples of vision blocks: trees or fences near an intersection, a big truck in the next lane, and fog, rain or darkness. It adds that a parked van can hide hazards ahead and that cresting a hill or rounding a sharp curve also leaves you unable to see what's coming. Because a truck beside you fits that list directly, the rider should be extra cautious whenever their view is blocked.
Why the other answers are wrong
- A. there are wet leaves or other debris on the road. — Wet leaves and debris are not included among the handbook's examples of things that block your view; the listed vision blocks are things like trees, fences, a large truck beside you, fog, rain or darkness.
- C. you are riding on a straight and clear road. — A straight, clear road is the opposite of a vision block, since the passage describes being unable to see ahead as the problem.
- D. All of the above — This cannot be right because the wet leaves and the straight, clear road are not vision blocks, so not every choice in the list applies.
Remember it
Ask yourself one question as you ride: can I see far enough ahead right now? If something is in the way of that view, treat it as a hazard.