对于胸部CT导向穿刺活检的论述，错误的是（）

A.利用目标扫描选择出最佳定位层面

B.穿刺活检的定位层面病变显示应最大、最清晰

C.穿刺时病人必须采取仰卧正位，保持不动

D.穿刺针穿入后，应于该层面扫描确认准确与否

E.穿刺针拔出，活检完毕，亦应继续扫几层

Questions 27～30

A. Their lecturer-student ratio is not reasonable.
B. Their staff is not interested in helping students.
C. Their lecture halls are not well equipped.
D. Their degrees are not accepted by employers.