Which part of the washer system should function properly to pass inspection?

Answer: B — The spray pattern

For the inspection of a vehicle's washer system, the spray pattern is crucial for proper visibility and safety. When the washer system is engaged, the fluid should be evenly distributed across the windshield to effectively remove dirt, debris, and other obstructions. A well-functioning spray pattern ensures that the driver can maintain clear visibility, especially in adverse conditions such as rain or when dirt accumulates. The other components, while important for the overall operation of the washer system, do not directly impact how effectively the washing process works in terms of clearing the windshield. The fluid reservoir must contain washer fluid to operate, the wiper arm connections need to be secure for the wipers to function, and the motor speed plays a role in the rate at which the washer fluid is applied. However, none of these aspects can compensate for an inadequate spray pattern. If the spray does not reach the windshield effectively, it compromises safety regardless of how well the other parts function. Thus, ensuring that the spray pattern is effective is key to passing the inspection.