Why is it risky to ride beside a row of parked cars?

Answer: B — Someone could open their door

Riding beside a row of parked cars is particularly risky because someone could unexpectedly open a car door into the path of the motorcycle. This situation, often referred to as "dooring," can catch a rider off guard and lead to a serious accident. Motorcyclists are more vulnerable than those in vehicles, and an open door can create a sudden obstacle that a rider may not have sufficient time or space to react to safely. While other factors—such as lane changes by cars or poor visibility—can contribute to risks while riding, the immediate danger presented by a car door being opened is a unique and specific threat that is not as easily controlled or anticipated. Consequently, it is crucial for motorcyclists to remain alert and maintain a safe distance from parked vehicles when riding to mitigate this risk effectively.