The correct answer is:
(a) True
The design of engines in an air-cooled system is indeed simpler because they do not require water jackets, coolant pumps, radiators, or associated plumbing, all of which are necessary in a water-cooled system. In an air-cooled engine, the engine's surface area is increased using fins or other structures to dissipate heat, and the cooling is achieved through the flow of air. This simplicity in design is one of the reasons air-cooled engines are often used in applications where space and weight are critical factors, such as in small engines, motorcycles, and aviation.