Question

Beijing ________ a lot in the past ten years. Now it has become one of the biggest modern ________ in the world.

1. A.
   changes; cities
2. B.
   changed; city
3. C.
   has changed; cities
4. D.
   had changed; cities

Answer 1

C
解析：
点拨：in the past ten years是现在完成时的标志；
one of后跟名词复数。