I don't think she is a nice woman. I'm _____ her empty talk. [ ]

A. grateful for

B. tired of

C. crazy about

D. concerned about

下列哪一项不是使人群易感性升高的因素

A．易感人口的迁入
B．免疫人口的死亡
C．新生儿增加
D．预防接种
E．免疫人口免疫力的自然消退