《传染病防治法》规定，国家对传染病实行的方针与管理办法是（）。
参考答案：预防为主，防治结合，分类管理
_____ is mentioned above, the number of the students in senior schools is increasing in this district. [ ]
A. Which
B. As
C. That
D. It
多项式a2﹣a+5减去3a2﹣4，结果是[ ]
A．﹣2a2﹣a+9
B．﹣2a2﹣a+1
C．2a2﹣a+9
D．﹣2a2+a+9
