单选

Moisture absorbed in the windings or condensed on the surface of electrical machinery insulation _____.

A.is good for long term preserving since most insulation is organic and contains some amount
B.lowers the insulation value and is a common cause of fault grounds in idle machines
C.will enhance insulation resistance only if it is fresh water and contains no salt
D.reduces the amount of current supplied or drawn by the machine so horsepower is limited

试题出自试卷《轮机部三管轮考试模拟题4(轮机英语)》

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