经血传播的感染性病原体有几种：（）
A.2；
B.3；
C.4；
D.5
参考答案：B
In order to earn money for his family, it is necessary for him to get a job.
A．it is necessary to get a job
B．it is necessary to find a job
C．he must get a job
D．a job must be found
物业管理项目的承接不包括下列( )项目。
A．全方位服务型管理B．顾问服务型管理C．自主服务型管理D．合资合作
