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單項(xiàng)選擇題

The working cycle of a four-stroke diesel engine consists of four events:（）
(1) compression
(2) expansion
(3) exhaust
(4) suctionThe correct sequence is

A.(4)-(2)-(3)-(1)
B.(4)-(3)-(1)-(2)
C.(4)-(3)-(2)-(1)
D.(4)-(1)-(2)-(3)

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