请选择ABCD6_2o'?8^:].R+|8h(P4v4Y/c1p5\6J3t*g ________ is known to all, China will be an ________ and powerful country in 20 or 30 years' time..{-x1m:x
A. That; advancing.{-x1m:x
B. This; advanced.{-x1m:x
C. As; advanced.{-x1m:x
D. It; advancing.{-x1m:x