—I don’t know          makes her different from others.

—Confidence, I think.

A．how is it that

B．how it is that

C．what is it that

D．what it is that

下列资料属于等级资料的是

A．白细胞计数

B．住院天数

C．门诊就诊人数

D．患者年龄

E．患者治疗结果评定(治愈、好转、有效、无效)