单选题The term diesel engine scavenging means（）Adelivering more air into the cylinder than it would normally receive during an ordinary charging processBforcing the products of combustion out of the cylinder with the fresh air chargeCcollecting the air charge at the cleanerDcombustion and expansion of hot gas
单选题
The term diesel engine scavenging means（）
A
delivering more air into the cylinder than it would normally receive during an ordinary charging process
B
forcing the products of combustion out of the cylinder with the fresh air charge
C
collecting the air charge at the cleaner
D
combustion and expansion of hot gas
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