单选题When subjected to high heat from a open flame, or an electric heating element, which of the listed refrigerants will break down and produce phosgene gas?（）ACO2BMethyl chlorideCR-22DSulphur dioxide
单选题
When subjected to high heat from a open flame, or an electric heating element, which of the listed refrigerants will break down and produce phosgene gas?（）
A
CO2
B
Methyl chloride
C
R-22
D
Sulphur dioxide
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