How can seat belts save lives?

Seat belts are designed primarily to keep occupants securely in their seats during a collision, which is the fundamental reason they save lives. In the event of a crash, the force of the impact can cause unrestrained individuals to be thrown from their seats or collide with the interior of the vehicle. A seat belt effectively restrains a person's body, minimizing movement and reducing the risk of severe injuries or fatalities. It spreads the forces of a crash over the stronger parts of the body and can significantly decrease the likelihood of ejection from the vehicle.

The other options do not directly contribute to the primary function of seat belts in terms of safety. While comfort can play a role in the willingness to wear a seat belt, it is not the determining factor in preventing injury during an accident. Preventing theft is unrelated to the primary safety purpose of seat belts, and reducing pedal fatigue is not something that seat belts are designed to address. Therefore, the role of a seat belt in providing physical safety during a collision is why it is essential for saving lives.