Final answer:
In most states, it is illegal to leave a child age 9 or younger alone in a vehicle to protect them from potential harm or danger. Leaving children unattended in a vehicle can expose them to extreme temperatures, risk of injury, or abduction.
Step-by-step explanation:
In most states in the United States, it is illegal to leave a child age 9 or younger alone in a vehicle. This is to protect children from potential harm or danger that they may face when they are not properly supervised. Leaving children unattended in a vehicle can expose them to extreme temperatures, risk of injury, or abduction.