How do seat belts provide safety during a crash?

Seat belts play a crucial role in enhancing the safety of vehicle occupants during a crash by helping to secure them in their seats and preventing ejection from the vehicle. In the event of a collision, the forces involved can be extremely violent, and unrestrained passengers are at a significant risk of being thrown from the vehicle, which often leads to severe injuries or fatalities. By keeping individuals firmly in place within the cabin of the vehicle, seat belts allow the vehicle's safety systems, such as airbags, to work effectively, providing further protection.

The other options refer to concepts that do not accurately reflect the primary function of seat belts. For example, while some modern vehicles do have inflatable seat belts that provide additional cushioning, this is not the standard function for most seat belts. The structural integrity of a vehicle is primarily ensured through its design and materials, not through seat belt usage. Lastly, although wearing a seat belt is a legal requirement that can lead to traffic violation penalties if not followed, the primary purpose is focused on enhancing personal safety, not compliance with traffic laws. Thus, the essence of seat belts is truly in their ability to secure occupants and mitigate the risks associated with collisions.