单选题In a four-stroke/cycle diesel engine, after the completion of the power stroke, the piston will move（）Aup and draw in a fresh air chargeBdown to burn off fuelCdown to compress the fuel air chargeDup and force out the exhaust gases
单选题
In a four-stroke/cycle diesel engine, after the completion of the power stroke, the piston will move（）
A
up and draw in a fresh air charge
B
down to burn off fuel
C
down to compress the fuel air charge
D
up and force out the exhaust gases
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