At what age must a child be in a booster seat until?

The correct answer is based on child passenger safety guidelines, which typically recommend that children use a booster seat until they reach the age of 8. This recommendation is established to ensure that children are properly secured in a vehicle in a way that protects them from injury during a crash. Booster seats help position the seat belt correctly across a child’s body, ensuring that the harness fits over the strongest parts of the child’s body.

Using a booster seat until at least 8 years old is crucial for the safety of the child, as it directly correlates with appropriate vehicle restraint systems designed for larger, older children. As children grow, their bodies develop and change, and the transition from a booster seat to a regular seat belt should be made only when the seatbelt fits properly without the assistance of a booster. This stage usually occurs when a child reaches a height of around 4 feet 9 inches, which often happens by ages 8 to 12, depending on the child.

The other answer choices do not align with the safety standard recommendations for the use of booster seats, making them less appropriate in the context of ensuring child safety in vehicles.