单选题Scavenging in a four-stroke/cycle diesel engine occurs during the （）.Alast part of the exhaust stroke, and the first part of the intake strokeBlast part of the intake stroke onlyCearly part of the injection stroke onlyDearly part of the power stroke
单选题
Scavenging in a four-stroke/cycle diesel engine occurs during the （）.
A
last part of the exhaust stroke, and the first part of the intake stroke
B
last part of the intake stroke only
C
early part of the injection stroke only
D
early part of the power stroke
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