与强直性脊柱炎的发病关系最为密切的因素是（）
A.肠道细菌感染
B.肺炎克雷伯杆菌
C.HLA-B27
D.链球菌感染
E.泌尿系感染
参考答案：C
— Is Shanghai bigger than Tokyo (东京)?
— No. Tokyo has over 30 million people, it is bigger than _____ in China. [ ]
A. any other city
B any other cities
C. any cities
D. any city
直接管理原则的要求。
