Bing Xin wrote her first article at the age of 19 and finished her last one at the age of 94. Through all those years, she _________.

1. A.
   had often studied
2. B.
   was always studying
3. C.
   studied hard
4. D.
   had always been studying

Bing Xin wrote her first article at the age of 19 and finished her last one at the age of 94. Through all those years, she _________.

A. had often studied                                              B. was always studying

C. studied hard                                                       D. had always been studying

Bing Xin wrote her first article at the age of 19 and finished her last one at the age of 94. Through all those years, she _________.

A. had often studied　　　　　　　 B. was always studying

C. studied hard　　　　　　　　　 D. had always been studying