piloteer的白勇题目-30题

30． Freedman's survey showed that people living in small towns and rural areas consider themselves no happier than do people living in big cities.
（A） no happier than do people living
（B） not any happier than do people living
（C） not any happier than do people who live
（D） no happier than are people who are living
（E） not as happy as are people who live

答案是A。不明白的是，为什么than后面要多个do？这是个什么语法现象啊？

Freedman's survey showed that people living in small towns and rural areas consider themselves no happier than consider people living in big cities.?

这是个什么结构啊？倒装？在对比的结构中倒装？是指小城市的人们认为他们不高兴的程度，高于在大城市的人们吗？

为什么不可以是：

Freedman's survey showed that people living in small towns and rural areas consider themselves no happier than people living in big cities.?