下列描述髓腔增龄性变化不正确的是（）
A.髓腔体积变小
B.根管变粗
C.根管变细
D.根尖孔变窄
E.髓角变低
参考答案：B
关于表皮萎缩正确的是（）
A.表皮突延伸
B.见于慢性皮炎
C.见于银屑病
D.见于硬化萎缩性苔藓
E.见于急性皮炎
Sixty percent of all Chinese are farmers and they are than people who live in the cities.
A. poor B. much poorer C. much richer
