How must the brake lights function on a moped?

The correct answer emphasizes the necessity for the brake lights on a moped to be fully functional when either brake is applied. This requirement plays a critical role in ensuring safety on the road, as it signals to other drivers when the moped is slowing down or coming to a stop. By having operable brake lights, it minimizes the risk of accidents by enhancing visibility and communication among road users.

In many jurisdictions, including South Carolina, the law mandates that all motor vehicles, including mopeds, are equipped with effective brake lights as a safety standard. This standard underscores the importance of being easily seen by other motorists, particularly in traffic or during low visibility conditions. Hence, functioning brake lights are not just a recommendation but a legal requirement for safe operation of a moped.