Final answer:
The object of a restraint system is indeed to keep vehicle occupants securely seated and prevent them from striking interior components, and modern safety features like airbags and crumple zones help reduce injury by increasing impact time.
Step-by-step explanation:
The statement that the object of a restraint system is to keep the vehicle's occupants securely seated during a collision and to prevent occupants from striking interior components such as a steering wheel or window is true. Among the safety features in modern vehicles that contribute to this objective are airbags and crumple zones.
Crumple zones are designed to deform in the event of a collision, which increases the time of impact. According to the physics concept of impulse, which is the product of the net force and the time over which it acts (Fnet ∆t), an increase in the time during which the force is applied results in a decrease in the force exerted on the occupants, thus reducing injuries.
This is explained by the fact that the overall momentum change will be the same, but spreading this change over a longer period reduces the force, thereby lessening the risk of serious injury. Therefore, the correct answer to the student's multiple-choice question is 'a. It reduces injury to the passengers by increasing the time of impact'.