腺瘤发病率最重要的独立决定因素是（）
A.患者年龄＞60岁
B.结肠癌家族史
C.腺瘤家族史
D.种族
E.性别
参考答案：C
“征免”栏应填：
A．照章征税
B．全免
C．进料加工
D．中外合作
—Your father's back home now, _____ he?
—Yes, he _____ been at home for half an hour. [ ]
A. isn't, has
B. hasn't, has
C. hasn't, is
D. isn't, is
