单选题Which of the listed chemicals can be routinely used to maintain the hygienic quality of potable water?（）AHydrochloric acidBChlorineCSulfuric acidDZinc chromate
单选题
Which of the listed chemicals can be routinely used to maintain the hygienic quality of potable water?（）
A
Hydrochloric acid
B
Chlorine
C
Sulfuric acid
D
Zinc chromate
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