Final answer:
The answer clarifies that it is necessary to use the shoulder belt for the seat to work properly in a crash situation and explains why.
Step-by-step explanation:
The statement 'It is not necessary to use the shoulder belt for the seat to work properly in a crash situation' is False. Using a shoulder belt is crucial for the seat to work properly during a crash. The shoulder belt, along with the lap belt, helps distribute and absorb the force of impact, reducing the risk of injury to the occupant.
Without a shoulder belt, the force would be concentrated on the lap belt, increasing the likelihood of serious injuries, such as being thrown forward or hitting the dashboard. By properly wearing both the lap and shoulder belt, the risk of injury during a crash is significantly minimized.