What is the primary function of the airbag in a car?

The primary function of the airbag in a car is to protect passengers during a crash. When a vehicle experiences a significant impact, the airbag inflates rapidly to create a cushion that absorbs some of the force of the collision. This helps to reduce the risk of injury by preventing passengers from striking hard surfaces inside the car, such as the steering wheel, dashboard, or side windows. The design and deployment of airbags are intended to work in conjunction with seat belts, providing an additional layer of safety for occupants.

While other choices include aspects that relate to vehicle operation or safety, they do not accurately capture the main purpose of an airbag, which is explicitly focused on passenger safety in the event of a collision.