给词语排序，并写出理由。

1．博士生  小学生  大学生  硕士生  中学生

     排序：                                                                                                 

     理由：                                                                                                 

2．儿子  曾祖父  父亲  祖父

     排序：                                                                                                 

     理由：                                                                                                 

3．国庆节  儿童节  劳动节  建军节  植树节

     排序：                                                                                                 

     理由：                                                                                                 

4．西安  中国  东亚  陕西  亚洲

     排序：                                                                                                 

     理由：                                                                                                

客观地确定目标人群的主要健康问题以及引起健康问题的行为因素和环境因素属于（）.

A.社会诊断

B.行为诊断

C.环境诊断

D.管理与政策诊断

E.流行病学诊断