单选题Wear occurring at the tips of the reduction gear teeth is usually the result of （）.Asurface fatigueBfretting corrosionCheavy overloadingDgear misalignment
单选题
Wear occurring at the tips of the reduction gear teeth is usually the result of （）.
A
surface fatigue
B
fretting corrosion
C
heavy overloading
D
gear misalignment
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