At what age and weight must a child be restrained in the rear seat?

The correct answer reflects the standards for child passenger safety, specifically focusing on the age and weight restrictions that apply to the rear seat of a vehicle. According to the North Carolina law, children must be restrained in a rear seat until they reach the age of 5 or weigh less than 40 pounds. This regulation is designed to enhance the safety of young passengers, as utilizing the rear seat can significantly reduce the risk of injury in the event of a crash.

In this context, option B is appropriate because it aligns with the guidelines stating that children 5 years of age and under who weigh less than 40 pounds should be properly secured in a rear seat. This approach prioritizes their safety by ensuring that they are in an area of the vehicle that offers the best protection.

Other options do not correctly reflect the combination of age and weight necessary for rear seat restraint, which is why they do not align with established guidelines. This highlights the importance of following legal requirements to promote the safety of children while traveling in vehicles.