可编程序控制器基本框架与扩展框架之间如果（），可以通过远程I/O口连接
A、距离较近
B、距离较远
C、与距离无关
D、其他
参考答案：B
Some of the famous pictures _____ taken are on display in the museum.[ ]
A. that was
B. what is
C. they are
D. which were
精子体部形态异常主要是指（）
A.着色异常
B.肿胀和不规则
C.皱缩和畸形
D.有异常颗粒
E.折断和分裂
