What is required for the rear fenders on a vehicle?

The requirement for rear fenders on a vehicle is that they should extend downward to the center of the wheel. This design is essential to ensure that debris kicked up by the tires does not strike other vehicles or pedestrians. Fenders that adequately cover the wheel area help prevent mud, water, and rocks from being thrown up onto the vehicle's body or the road, thus contributing to safety on the road.

By extending downward to the center of the wheel, the fenders provide adequate protection against these hazards while also enhancing the vehicle's aesthetics and compliance with safety regulations. Proper fender coverage is crucial, especially in terms of vehicle inspections, where adherence to safety standards is assessed.

The other options describe characteristics that do not fully address the safety and functional requirements governed by the vehicle's design. For instance, having a fender that merely covers the top of the wheels may not adequately protect against debris being thrown from the sides, and being flush with the body could compromise the clearance needed for proper tire function and turning radii. Similarly, ensuring that the fender does not extend beyond the wheelbase focuses more on design aesthetics than on the necessary coverage to maintain road safety and vehicle compliance.