Airbags are
- legally required in all commercial vehicles.
- dangerous if your chest is too close to the steering wheel. ✓
- a good alternative to seatbelts.
- unnecessary.
Answer: B. dangerous if your chest is too close to the steering wheel.
Airbags are dangerous if your chest is too close to the steering wheel.
Why this is the answer
The handbook says you must keep at least 25 cm (10 in) between your breastbone and the airbag unit in the steering wheel. Keeping that distance reduces the risk of injury when the bag deploys. Sitting closer than that puts you in the zone where the deploying bag can hurt you, which is why the correct choice is the one about being too close to the wheel.
Why the other answers are wrong
- A. legally required in all commercial vehicles. — The handbook actually says most large trucks aren't equipped with airbags, so it does not treat them as a legal requirement for commercial vehicles.
- C. a good alternative to seatbelts. — The handbook states that even with airbags you must wear your seatbelt, and that airbags can seriously injure unbelted occupants, so they are not a substitute.
- D. unnecessary. — The passages discuss how to sit safely with an airbag and how to adjust head restraints, so they treat airbags as something to manage, not as unnecessary.
Remember it
Picture a ruler between your chest and the wheel: if your breastbone is closer than that gap, slide the seat back.