A two-cycle gasoline engine is characterized by which statement?

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

Answer: (C)

Two-stroke engines complete their power cycle in two piston movements, so they fire a power stroke with every revolution. That design leads to a simpler overall construction because there’s no camshaft or valve train in many designs; intake and exhaust are handled by ports in the cylinder walls rather than by valves. This simplicity is the most characteristic feature when comparing to a four-stroke engine.

From the given statements, the one that best captures this idea is that a two-stroke engine is simpler in construction. The others aren’t reliable descriptors: power output isn’t guaranteed to be exactly twice that of a four-stroke and depends on many factors; two-stroke engines do not have to have two cylinders (single-cylinder versions exist); and not all designs require exhaust valves (many use exhaust ports instead).