求助！PREP07-97 关于while+Ving省略结构

濄濄鸣人

Industrializationand modern methods of insect control have improved the standard of living around the globe while at the same time they have introduced some 100,000 dangerous chemical pollutants, having gone virtually unregulated since they were developed more than 50 years ago.

(A) while at the same time they have introduced some 100,000 dangerous chemical pollutants, having

(B) while at the same time introducing some 100,000 dangerous chemical pollutants that have

(C) while they have introduced some 100,000 dangerous chemical pollutants at the same time, which have

(D) but introducing some 100,000 dangerous chemical pollutants at the same time that have

(E) but at the same time introducing some 100,000 dangerous chemical pollutants, having

答案是B 我想问的是while+Ving省略结构 只对while有效么？ 比如其他的转折词如nevertheless 有这种ving省略么？  谢谢！

濄濄鸣人

Ding!! 帮帮我。。。

0905030219

至少我看到的都是有关于while的，其他的也不太清楚了·~~请NN回答吧~~~