一种商品畜产品大幅度的价格变动只引起供给量较小幅度的变动，说明这种商品（）
A、富有弹性
B、缺乏弹性
C、完全有弹性
D、完全无弹性
参考答案：B
Peter hardly had time for concerts at that time, ________? [ ]
A. wasn't he
B. was he
C. didn't he
D. did he
直肠中、上段癌肿最好采用（）
A.直肠指检
B.乙状结肠镜
C.直肠镜
D.钡剂灌肠
E.纤维结肠镜检
