Do passengers in a vehicle have to wear seat belts?

Answer: A — Yes

All passengers in a vehicle should wear seat belts to ensure their safety. This includes both those sitting in the front and back seats, regardless of age. While it is a legal requirement for those under 18 to be wearing seat belts, it is important for everyone to wear them in order to prevent serious injuries in the event of an accident. Therefore, options B, C, and D are incorrect as they limit the practice of wearing seat belts to certain individuals.