Recently,thereis

问题详情：

 Recently, there is ____ boom（繁荣）in population mobility and according to ____ national population survey of 2004, 17 percent of the population move every year.

      A. the; a      B. a; the      C. /; a        D. the;/

【回答】

B

知识点：冠词

题型：选择题