单选题Refrigerant entering the compressor of a refrigeration system should be in which of the following conditions?（）ASub-cooled liquidBSub-cooled vaporCSuperheated vaporDLiquid
单选题
Refrigerant entering the compressor of a refrigeration system should be in which of the following conditions?（）
A
Sub-cooled liquid
B
Sub-cooled vapor
C
Superheated vapor
D
Liquid
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