Final answer:
The subject of this question is Health. The correct answer is up to 20 pounds. This law is in place to ensure the safety of young children while traveling in a vehicle.
Step-by-step explanation:
The subject of this question is Health.
The question is about a law that requires a rear-facing safety seat secured in the back seat for a child weighing a certain amount. According to the information provided, the correct answer is a. up to 20 pounds.
This law is in place to ensure the safety of young children while traveling in a vehicle.