单选题Which of the following statements is true concerning carbon dioxide when used as a fire extinguishing agent?（）ACarbon dioxide is corrosive when exposed to fireBCarbon dioxide should be applied slowly to a large engine room fireCIts total cooling effect is far greater than waterDIts smothering effect is excellent for class B fires
单选题
Which of the following statements is true concerning carbon dioxide when used as a fire extinguishing agent?（）
A
Carbon dioxide is corrosive when exposed to fire
B
Carbon dioxide should be applied slowly to a large engine room fire
C
Its total cooling effect is far greater than water
D
Its smothering effect is excellent for class B fires
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