What should you NEVER do with the shoulder harness while buckling up?

The correct response emphasizes the importance of correctly positioning the shoulder harness while buckling up for safety. Positioning the shoulder harness under your arm is dangerous because it does not provide the necessary protection in the event of a collision. The shoulder harness is designed to distribute crash forces across the strongest parts of the body—such as the chest and shoulders. When the harness is placed under the arm, it can lead to severe injuries during a crash, as it may allow the occupant to move forward too far, potentially causing head and neck injuries.

The other options also highlight unsafe practices but do not specifically address the critical function of the shoulder harness in protecting the upper body in a crash. For example, wrapping the harness around your waist does not allow it to function as intended, crossing it behind your back can create a similar risk of injury, and wearing it loosely reduces its effectiveness. Each of these practices compromises the safety benefits of the harness, but positioning it under your arm is particularly hazardous, making it essential to avoid.