— Have you any idea where he comes from?

— Judging by his __________, he must be from Hunan.

A．tone

B．style

C．voice

D．accent

25℃时在五份蒸馏水中分别加入适量的下列物质，所得实验结果如下表所示：

加入物质后水的电离程度由大到小排列顺序正确的是

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A.α3>α1>α5>α4>α2

B.α4>α2>α5>α3>a1

C.α2>α4>α5>α1>α3

D.α1>α3>α5>α2>α4