单选题Noise in a refrigeration compressor can be caused by ().Aworn bearings and piston pinsBslugging due to flooding backCtoo much oil in circulationDAll of the above

单选题
Noise in a refrigeration compressor can be caused by ().
A

worn bearings and piston pins

B

slugging due to flooding back

C

too much oil in circulation

D

All of the above


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