请教 prep 75

75.  A recent poll indicates that many people in the United States hold a combination of conservative and liberal political views; i.e., they denounce big government, saying government is doing too much and has become too powerful, while at the same time supporting many specific government programs for health car, education, and environment.

A. they denounce big government, saying government is doing too much and has become too powerful, while at the same time supporting

B. they denounce big government—they say that government is doing too much and has become too powerful—but supporting at the same time

C. they denounce big government, they say that government is doing too much and it has become too powerful, while they support at the same time

D. while they denounce big government, saying that government is doing too much and has become too powerful, at the same time supporting

E. while they are denouncing big government—they say that government is doing too much and it has become too powerful—supporting at the same time

答案是A, 请问while are the same time supporting为什么不是while at the same time they support? ,while难道不应该接一个独立主谓机构吗?

我刚刚查了LDoce, 发现"say"真的可以省略"that":

▶EXPRESS SOMETHING IN WORDS◀
to express an idea, feeling, thought etc using words
say (that)
A spokesman said that the company had improved its safety standards.

I always said I would buy a motorbike when I had enough money.

不是说口语或者其他的英语考试都可以省，GMAT不能省that么？

请问一下这里A的的while supporting是和denounce平行还是和saying平行？我一上来就排除了A，因为觉得他逻辑上应该和denounce平行，但是形式上和saying平行

后来我就想，是不是while (they are) supporting省略了they are, 其实是they are 和denounce 平行？

同样有楼上的困惑，

while at the same time supporting many specific government programs for health car, education, and environment.

到底是和谁平行啊，感觉不应该和saying 平衡吧？期待牛牛的出现

同问楼上问题