以下各项对头痛病因病机概括较全面的是（）.
A.外感和肾虚
B.肾虚和瘀血
C.外感和内伤
D.气血不足
E.久病体虚
参考答案：C
—Where______my keys?
—Sorry,______. [ ]
A. is; I don't know
B. are; I don't know
C. are; it's here
D. is; it's here
什么是Rh血型？
