单选题When fuel enters the crankcase of a diesel engine, it （）Adilutes the lube oil and reduces its viscosityBforms sulfuric acid in the lube oilCcauses pitting and failure of the bearingsDcauses sludge deposits on valve stems
单选题
When fuel enters the crankcase of a diesel engine, it （）
A
dilutes the lube oil and reduces its viscosity
B
forms sulfuric acid in the lube oil
C
causes pitting and failure of the bearings
D
causes sludge deposits on valve stems
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