All children age __________ and under must use a restraint device when riding in a motor vehicle.

The correct answer is based on Florida law, which mandates that all children age 5 and under must be secured in a proper restraint device when riding in a motor vehicle. This is crucial for their safety as children are at a much higher risk of injury in the event of a crash if not properly restrained.

Choosing any age higher than 5 would not align with the current legislation designed to protect younger children, as those ages may not meet the legal requirement for using a restraint device. The law reflects an understanding that younger children, due to their smaller size and developmental stage, need specific types of safety restraints, such as car seats or booster seats, to minimize the risk of injury.