单选题As the refrigerant passes through the valve orifice, its pressure is reduced and part of the refrigerant turns into （）.AliquidBoily mixtureCemulsionDvapor
单选题
As the refrigerant passes through the valve orifice, its pressure is reduced and part of the refrigerant turns into （）.
A
liquid
B
oily mixture
C
emulsion
D
vapor
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