What must a passenger under 18 years of age have when riding your motorcycle?

Answer: B — Footrests, helmet, and seat

For a passenger under 18 years of age riding a motorcycle, it is crucial that they have footrests, a helmet, and a seat. This requirement is designed to ensure the safety and proper seating position of the passenger during the ride. The helmet protects against head injuries, which are a significant risk in motorcycle accidents. Footrests provide a stable place for the passenger's feet, preventing them from dangling and increasing the risk of accidents or injuries. Additionally, a seat ensures that the passenger is seated securely and not at risk of falling off the motorcycle. The options offering just a helmet and gloves or only a seat do not meet the essential safety standards for a young passenger. Skipping the footrests would also pose a significant safety risk, especially for passengers who might not be able to maintain a stable position without them. Thus, having all three components—footrests, helmet, and seat—ensures that young passengers are as safe as possible while riding.