有两短周期元素X和Y,可组成化合物XY3,当Y的原子序数为m时,X的原

有两短周期元素XY,可组成化合物XY3,当Y的原子序数为m时,X的原子序数为m4m4m8m2m6,其正确的组合是(        )

A①②④                          B①②⑤

C①②③⑤                              D①②③④⑤

答案

D

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