All persons 12 years old and younger aboard a boat less than 26 feet are required to ______ when the boat is underway.

The requirement for all persons 12 years old and younger aboard a boat less than 26 feet to wear a PFD (Personal Flotation Device) when the boat is underway is rooted in safety regulations aimed at protecting young passengers. This rule is established to minimize the risk of drowning in the event of an accident or unexpected situation on the water. PFDs are designed to keep individuals buoyant and increase their chances of survival if they fall overboard or if the boat capsizes.

By mandating that children wear a PFD, the law helps ensure their safety, given their smaller size and potentially less swimming ability compared to adults. It is a precautionary measure that emphasizes the importance of personal safety gear while engaging in boating activities.

While staying seated can be a good practice during navigation, it is not a law that specifically applies in the same way that PFD requirements do. Similarly, while taking a boating safety course or being supervised by an adult are both beneficial safety practices, they do not address the immediate safety needs related to being on the water in a boat under 26 feet. Thus, the requirement to wear a PFD is the most appropriate and crucial regulation in this context.