单选题The most common cause of scale formation in an auxiliary boiler is （）Aconcentrations of calcium sulfate in the boiler waterBfuel oil in the feed waterCimproper treatment of the feed water with calcium sulfateDexcessive feed water alkalinity
单选题
The most common cause of scale formation in an auxiliary boiler is （）
A
concentrations of calcium sulfate in the boiler water
B
fuel oil in the feed water
C
improper treatment of the feed water with calcium sulfate
D
excessive feed water alkalinity
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