What factor increases the risk of losing control of a motorcycle?

Answer: B — Carrying a passenger

Carrying a passenger increases the risk of losing control of a motorcycle due to the additional weight, which affects the motorcycle's balance and handling. When a motorcycle is designed to be operated by one person, adding a passenger alters the center of gravity and can make the bike less stable, especially during turns or sudden maneuvers. This increased weight can also impact stopping distances and acceleration, making it more challenging for the rider to maintain control. Moreover, the presence of a passenger may lead to miscommunication between the rider and the passenger regarding movements, which can further complicate controlling the motorcycle. Effective weight distribution and the ability to react to changes in balance are crucial for safe riding, and adding a passenger changes these dynamics significantly.