A two-cycle gasoline engine is simpler than a four-cycle engine in construction.

• A. produces twice the power of a four cycle
• B. must have two cylinders
• C. requires exhaust valves
• D. is simpler than a four cycle engine in construction

Answer: (D)

Two-cycle engines are built with fewer moving parts because they don’t rely on a valve train. Intake and exhaust are controlled by the piston’s position and simple ports or scavenging passages, so there’s no camshaft, timing gears, or valve assemblies to complicate the design. That simplicity in the mechanism is what makes the engine construction inherently easier and lighter than a four-cycle engine.

Power output isn’t inherently double the power of a four-stroke; it depends on displacement, operating speed, and efficiency, so that claim isn’t guaranteed. A two-cycle engine also doesn’t have to have two cylinders—single- or multi-cylinder configurations are common. And while many two-stroke designs use ports instead of exhaust valves, that’s part of the simpler construction rather than a requirement to have valves. So the idea that a two-cycle engine is simpler in construction is the best fit.