When passing a row of parked cars, a motorcycle operator should be ready for which possible situation?

When passing a row of parked cars, a motorcycle operator should be particularly alert to the possibility of a motorist unexpectedly pulling out of a parking space. This situation is critical because vehicles parked along the curb may not be easily visible until they begin to move, and drivers are often unaware of motorcyclists when they open their doors or back out. As a result, the operator must maintain a safe distance from the row of parked cars and be prepared to react quickly to avoid a collision if a car enters their path.

Being vigilant in this scenario helps ensure the safety of both the motorcyclist and the vehicle driver, as well as any bystanders. The other options, while relevant to safe riding, do not encompass the immediate risk associated with moving vehicles in close proximity to parked cars. For example, pedestrians may cross streets at unexpected times, but the most pressing risk in this specific scenario stems from vehicles maneuvering from parking spaces.