单选题The sudden reduction of pressure occurring within the crankcase of a refrigeration compressor during starting causes the （）.Asudden evaporation of wax crystals in the lubricantBsudden evaporation of entrapped air in the lubricantCrelease of refrigerant from the oil/refrigerant mixtureDrelease of dissolved lubricant from the refrigerant
单选题
The sudden reduction of pressure occurring within the crankcase of a refrigeration compressor during starting causes the （）.
A
sudden evaporation of wax crystals in the lubricant
B
sudden evaporation of entrapped air in the lubricant
C
release of refrigerant from the oil/refrigerant mixture
D
release of dissolved lubricant from the refrigerant
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