请教一道今天模考遇到的SC

Not only did the systematic clearing of forest in the United States create farmland(especially in the Northeast) and gave consumers relatively inexpensive houses and furniture, but it also caused erosion and very quickly deforested whole regions.

A. Not only did the systematic clearing of forest in the United States create farmland(especially in the Northeast) and gave consumers relatively inexpensive houses and furniture, but it also

B. Not only did the systematic clearing of forest in the United States create farmland(especially in the Northeast), which gave consumers relatively inexpensive houses and furniture, but also

C. The systematic clearing of forest in the United States, creating farmland(especially in the Northeast) and giving consumers relatively inexpensive houses and furniture, but also

D. The systematic clearing of forest in the United States created farmland(especially in the Northeast) and gave consumers relatively inexpensive houses and furniture, but it also

E. The systematic clearing of forest in the United States not only created farmland(especially in the Northeast), giving consumers relatively inexpensive houses and furniture, but it

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此题选D.我选了E........我想问的是，not only..., but also...这个句式到底要怎么用？从这道题看来，似乎not...only可以不出现的样子....我搞不清了

请各位高手帮忙！！！！ 

恩。。。有道理~~

那也就是说如果考点是not only...but also...的话，一定要同时出现喽？

能找到not only but also用法中省略also的例句吗

E中有改变句意不是farmland带来房子和家具 觉得应该是The systematic clearing of forest

但我想不清楚it的指代问题 为什么 即使前半句的单数名词也有好几个