—       you did ?

— No, in fact, I didn't need to.[ ]

A. What is that    

B. That is what  

C. Is that what  

D. Is what that

年龄、性别、遗传、不良生活方式等影响药物使用安全的因素属于（）

A．药物因素

B．患者因素

C．医师因素

D．药师因素

E．护士因素