Mark the letter A, B, C, or D on...

Câu hỏi: Mark the letter A, B, C, or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions.
That inventors in the stock market enjoys increases and suffer declines is simply a fact of the financial market, and a small inventor is not too excited about the former or crestfallen about the latter.

A. enjoys    

B. declines 

C. former    

D. crestfallen