Which of the following is a common requirement of local child passenger safety laws?

The common requirement of local child passenger safety laws is that children must use an appropriate child restraint system. This principle is rooted in safety guidelines established by organizations like the American Academy of Pediatrics, which advocate for the use of age- and size-appropriate restraints to ensure that children are adequately protected while traveling in vehicles.

Using an appropriate child restraint system, such as a car seat or booster seat, reduces the risk of injury in the event of an accident significantly. Laws generally stipulate that these restraints must be used until children reach a certain age or size, ensuring they are properly secured as per safety guidelines.

In contrast, the other options either do not align with safety recommendations or lack enforcement in many jurisdictions. Children sitting in the front seat is discouraged until they reach an appropriate age and size due to the added risk of airbag deployment and proximity to the dashboard. Simply using seat belts is not adequate for younger children who may not fit properly in standard adult seat belts. Lastly, allowing children to travel without any restraints contravenes basic safety protocols and is illegal in most areas. Hence, the emphasis on using an appropriate child restraint system is a critical element of child passenger safety laws.