As PM2.5 readings reached as high as 900 in some cities, people are more _____ to get lung cancer in such conditions. 

A．probable

B．perhaps

C．possible

D．likely

( )是指国家行政机关根据法律和行政法规在其职权范围内制定的关于行政管理的规范性文件。

A．宪法
B．法律
C．地方性法规 D．行政规章