大牛们,请教一道语法题

如下:  

         While some propose to combat widespread illegal copying of computer programs by attempting to change people's attitudes toward pirating, others by suggesting reducing software prices to decrease the incentive for pirating, and still others by calling for the prosecution of those who copy software illegally.

(A)  by suggesting reducing software prices to
                decrease the incentive for pirating, and still
                others by calling

(B)  by suggesting the reduction of software prices
                to decrease the incentive for pirating, and still
                others call

(C)  suggest the reduction of software prices for
                decreasing the incentive for pirating, and still others call

(D)  suggest the reduction of software prices to
                decrease the incentive for pirating, and still
                others by calling

(E)  suggest reducing software prices to decrease the
                incentive for pirating, and still others are
                calling

Choice E, the best answer, uses constructions that are parallel to some propose', others suggest. . . , and still others are calling .... Choices A and B immediately lose the parallel construction, and also produce sentence fragments, by shifting to by suggesting ... and by calling .... Choice B starts like choice A and then shifts back to the verb call, losing the parallel with the second part (by suggesting). Choices C and D correctly begin the second part of the parallel by using suggest. Choice C, however, introduces the nonidiomatic for decreasing, which creates some difficulty in meaning. Choice D loses parallel construction in the third part by shifting to by calling.

那位大牛能为小女指点迷津,感激不尽,谢谢. 

这个 by+doing.....by+suggest+doing........still others are+doing.....

这个是什么语法什么逻辑？请高人指点，我甚至怀疑答案是否有错，谢谢了

你是否确认你编辑的题目与原题一样！

此句划线部分应该包括前面的by，可能是你看错题了。

此句考得语法点：

1. 并列结构

2. some .... others .... others 结构

感谢楼上二位热心人的解答。

抱歉，正如楼上所说，划线应该包含by, 但是还有一个问题，后面的still others are calling for.....，为什么不是still others call for呢？