单选

A disadvantage of a four-stroke/cycle diesel engine is ________.

A.higher working temperature of piston and cylinder
B.the use of scavenge ports
C.fewer power strokes per revolution of the crankshaft
D.part of the fuel is burned as the piston is moving away from top dead center

试题出自试卷《海船船员考试轮机部三管轮模拟题6(轮机英语)》

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