Prep 2-43 关于to thus keep的问题

Although ice particles in the upper atmosphere benefit Earth in that they reflect and absorb solar radiation, acting as a global thermostat and thus keeping Earth from either burning up or freezing over, they also accelerate the destruction of the ozone layer by reacting with chlorofluorocarbons (CFC's).  [A]
(A) acting as a global thermostat and thus keeping Earth from either burning up or freezing over, they also accelerate
(B) acting as a global thermostat and thus keeping Earth either from burning up or freezing over, while also accelerating
(C) act as a global thermostat and thus keep Earth from either burning up or freezing over, while also accelerating
(D) they act as a global thermostat that thus keeps Earth either from burning up or freezing over, even though it also accelerates
(E) they act as a global thermostat to thus keep Earth from either burning up or freezing over, but they also accelerate

对于E选项的to thus keep earth，prep语法笔记上解释说：thus副词不能连接并列的谓语act,keep(应将to改为连词and)

我的看法是，act和keep是有一种承接因果关系，所以改为act as a global thermostat to keep应该是可以的，这里错是错在不定式中间是不能加东西的，而这里加了thus。至于to是否要改为thus不是根本问题。

另外想问一下 act as sth. to do这样的搭配正确吗？

what about:

Let us wait and see.

no one say 'Let us wait to see'

Hi，aeoluseros

什么叫“目的性语气的强加”？

E的问题在于破坏句子主干：although...(benefit), they (another benefit)... but (destruction)...，

感觉是although和they是同一个高度

A选项强调了：although...(benefit) acting (another benefit)..., they (destruction)...

正确的将although的好处和destruction的坏处进行对比，句子的平衡性更好