What should be done when approaching parked vehicles?

Answer: B — Come to a complete stop

Approaching parked vehicles can be dangerous, as there may be a driver or passenger who may suddenly open their door. It is important to slow down and come to a complete stop when approaching parked vehicles to ensure the safety of both the cyclist and the driver or passenger in the parked vehicle. Passing on the left or right may not give enough space for the opened door, and using the horn may startle the driver or passenger and cause them to open the door in a rush. Therefore, option B, coming to a complete stop, is the safest and most responsible choice when approaching parked vehicles.