单选题An orifice-check valve placed in a hydraulic system is used to（）Aregulate the fluid flow in either directionBrestrict movement of hydraulic fluid in one direction, but allow free movement in the other directionCallow free movement of hydraulic fluid in both directionsDallow a restricted fluid flow in one direction only
单选题
An orifice-check valve placed in a hydraulic system is used to（）
A
regulate the fluid flow in either direction
B
restrict movement of hydraulic fluid in one direction, but allow free movement in the other direction
C
allow free movement of hydraulic fluid in both directions
D
allow a restricted fluid flow in one direction only
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