What can be inferred about the relation between crash severity and restraint system usage?

Higher usage of restraint systems, such as seat belts and airbags, is associated with a reduction in crash severity. This correlation can be explained by the fundamental role that these safety features play in protecting occupants during a collision. Restraint systems are designed to minimize movement inside the vehicle, thus reducing the risk of serious injuries and fatalities by restraining occupants in their seats during an impact.

Statistical data and research studies consistently show that when occupants utilize seat belts, the likelihood of sustaining severe injuries decreases significantly. The primary purpose of these systems is to mitigate the force of a crash and help keep individuals safely within the protective structure of the vehicle, thereby enhancing overall safety.

The other options do not align with established principles in traffic safety. The assertion of no observed relation overlooks the wealth of studies demonstrating the beneficial impact of restraint systems. Claiming that lower usage leads to improved outcomes contradicts the fundamental safety principles and data that advocate for consistent usage of these systems to enhance survival rates. Additionally, stating that restraint systems only affect passengers and not drivers fails to recognize that these systems are designed for all occupants, including drivers, playing a critical role in their safety during a crash.