请教语法题，thanks

After several years of rapid growth, the healthy care company became one of the largest health care providers in the metropolitan area, while it then proved unable to handle the increase in business, falling months behind in its payment to doctors and hospitals.
A. while it then proved unable to handle the increase in business, falling months behind in its payment to
B. while it then proved unable to handle the increase in business and fell months behind in its payment to
C. but then it proved unable to handle the increase in business, falling months behind in its paying
D. but then proving unable to handle the increase in business, falling months behind in paying
E. but then proved unable to handle the increase in business, falling months behind in paying
这题选E， 我选A while 为什么不对？

Unearthed in China, fossils of feathered dinosaurs offer the most dramatic evidence yet discovered of the close evolutionary relationship between dinosaurs and birds.
A. offer the most dramatic evidence yet discovered of the close evolutionary relationship between dinosaurs and birds
B. offer evidence more dramatic than what has yet been discovered of the close evolutionary relationship between dinosaurs and birds
C. offer more dramatic evidence of the close evolutionary relationship than any yet discovered between dinosaurs and birds
D. have offered the most dramatic evidence of the close evolutionary relationship between dinosaurs and birds that have yet been discovered
E. have offered more dramatic evidence than any that has yet been discovered of the close evolutionary relationship between dinosaurs and birds
  Answer: A
我觉得A   yet 连接 offfer 和 discovered 两个动词，而 fossils 不能执行discovered 这个动作啊？