单选

Excessive alkalinity of the water in an auxiliary boiler can cause _____.

A.caustic embrittlement of the boiler metal
B.acidic corrosion of the boiler metal
C.hard scale deposits on the boiler tubes
D.etching of the heat exchange surfaces

试题出自试卷《海船船员考试轮机部三管轮模拟题4(轮机英语)》

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