我几道gmat语法题希望高手帮忙讲解一下吧

我几道gmat语法题希望高手帮忙讲解一下吧
In the 1970's,since birds were overcome by pollution,and routinely falling from the sky above Los Angeles freeways,this prompted officials in California to devise a plan that reduced automobile emissions.
A:since birds were overcome by pollution,and routinely falling from the sky above Los Angeles freeways,this prompted officials in California to devise a plan that reduced
B:since birds that had been overcome by polution were routinely falling from the sky above Los Angeles freeways,it prompted officials in California to devise a plan that would reduce
C:birds had been overcome by pollution and routinely fell from the sky above Los Angeles freeways,prompting officials in California to devise a plan that reduced
D:birds overcome by pollution routinely fell from the sky above Los Angeles freeways,prompting officials in California to devise a plan to reduce
E:birds overcome by pollution and routinely falling from the sky above Los Angeles freeways wre prompting officials in California to devise a plan to reduce
2:Floating in the wataers of the equatorial Pacific,an array of buoys collects and transmits data on long-term interactions between the ocean and the atmosphere,interactions that affect global climate.
A:atmosphere,interactions that affect
B:atmosphere,with interactions affecting
C:atmosphere that affects
D:atmosphere that is affecting
E:atmosphere as affects
第一题答案给的是D,我想问D中就没有谓语动词啊，怎么能成句子呢

1 AB that、it无指代内容；C overcome by pollution 和fell 无前后关系,时态错；E and不平行,选D
2 选A,that引导定语从句时指代前面紧接着的那个词,此此句里affect climate 的是interactions而非atmosphere,故重复interaction,同位语从句