求助prep1-130语法，请大家赐教

130. (31416-!-item-!-188;#058&004490)

Industrialization and 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, and

have

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

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

(A)
                    整个句子中的两个代词they指代对象不一致，划线部分they没有指代对象，未划线部分的they指

代的是pollutants；having gone…分词结构有作伴随状语修饰have introduced的歧义，而不是作

pollutants的定语。

(B)  正确，while +    现在分词结构表示“与…同时”的含义；that引导定语从句修饰紧临的名词pollutants。

(C)  整个句子中的两个代词they指代对象不一致，原因与A选项相同；and have gone…在语法上应该

与主语谓语have improved并列，但在逻辑上应该是指pollutants，这种用法是错误的。

(D) but +  现在分词的用法错，而且but表达的是转折含义，原句并无此含义。

(E) but表达了与原句不同的转折含义，having gone…分词结构有作伴随状语修饰have introduced的

歧义，而不是作pollutants的定语。

求助一下大家，这里while既然表示的是一个同时的概念，那B 中at the same time岂不是很明显的重复吗？这道题目我选的是E，请大家赐教