________, great changes ________ in China.

1. A.
   In 1990's, have been taken place
2. B.
   In the 1990s', have been taken place
3. C.
   In the 1990s, have taken place
4. D.
   In 1990s, have taken place

 In the past twenty years great changes _______in China.

A. were taken place      B. have been taken place 

C. have taken place      D. were happened

253. Great changes ________ for the latest twenty years in China.

A. have taken place                                  B. have been taken place

C. have happened                           D. have taken the place of