In the mid-1970's.since birds were overcome by pollution,and routinely falling from the sky above LA freeways,this prompted officials in CAlifornia to edvise a plan that reduced automobile emissions.
A. Since birds that had been overcome by pollution were routinely falling from the sky above LA freeways,this prompted officials in California to devise a plan that reduced
B.since birds that had been overcome by pollution were routinely falling from the sky above LA freeways,it prompted officials in California to devise a plan that would reduce
C.birds had been overcome by pollutionand routinely fell from the sky above LA freeways,prompting officials in California to devise a plan that reduced
D.birds overcome by pollutioin routinely fell from the sky above LA freeways,prompting officials in California to devise a plan to reduce
E.birds overcome by pollution and routinely falling from the sky above LA freeways were prompting officials in Cali. to devise a plan to reduce
ANS: D
有個疑問。。。D中 ,prompting... = birds prompt...
但應該是這整個事件促使官員...而不是birds 去prompt
是這樣嗎?? thanks