单选题Operating a propulsion diesel engine at less than 30% of designed normal load for prolonged periods will result in （）.Adecreased fuel consumption per brake horsepowerBmore complete cylinder scavengingCextended valve lifeDcarbon formation on combustion chamber surfaces
单选题
Operating a propulsion diesel engine at less than 30% of designed normal load for prolonged periods will result in （）.
A
decreased fuel consumption per brake horsepower
B
more complete cylinder scavenging
C
extended valve life
D
carbon formation on combustion chamber surfaces
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