转辙装置中各种连接杆调整丝扣的余量不得小于（）。
A、5mm
B、8mm
C、10mm
D、7mm
参考答案：C
It is Tom rather than you who _____. [ ]
A. is to be blamed
B. are to blame
C. is to blame
D. are to be blamed
胰腺癌检查和诊断的金标准是（）
A.B超
B.X线
C.CT
D.ERCP
