It is said that this project will take two to three years and cost about 200 million yua

问题补充：

It is said that this project will take two to three years, and cost about 200 million yuan.

A. mainly

B. regularly

C. approximately

D. frequently

答案：

A. mainly

B. regularly

(答案→)C. approximately

D. frequently

解析：考查副词：A. mainly主要的B. regularly有规律地C. approximately 大约D. frequently频繁地，句意：据说，这个项目大约要两到三年，耗费2亿。选C。