单选题Increased internal leakage, in addition to poor hydraulic system response,and inadequate lubrication, is the result of （）.Apump bearings in poor conditionBexcessively worn actuator-piston packingCbroken directional control valve centering springsDlow hydraulic oil viscosity
单选题
Increased internal leakage, in addition to poor hydraulic system response,and inadequate lubrication, is the result of （）.
A
pump bearings in poor condition
B
excessively worn actuator-piston packing
C
broken directional control valve centering springs
D
low hydraulic oil viscosity
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