Not only did the systematic clearing of forests 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.

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

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

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

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

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

the anwser is A.Why not D?

首先答案是b a的倒装把did提前 用gave是明确的语法错误

d只有but also

一般来说，not only... but also...连接的是两个递进关系的成分， 题目中的是两个对立成分；

B的，which...从句有问题， 是"the systematic clearing of forests"  "gave consumers relatively inexpensive houses and furniture"  而不是farmland!  按照GMAC的语法解释，修饰词/从句必须紧邻被修饰部分； 再者，create farmland和give consumers inexpensive stuff...是对等的， 应该用and连接才符合parallelism!

A的did gave， 如果不是typo的话， 的确很低级！ 改成give， a就无可非议；

这样的话， 只有d 语法和逻辑都说的过去；