年轻女性,性交后出血,与下列哪项疾病无关()
A.宫颈糜烂
B.宫颈癌
C.宫颈息肉
D.宫颈肥大
E.急性 * * 炎
参考答案:D
—How do you usually go to school?
—_____ my mother's car. [ ]
A. By
B. With
C. In
D. For
简述统计指数的作用及分类。