When checking a mooring line，you should（）.

A.ensure the bight is not fouled between the ship and the dock by taking up slack

B.pay out slack smartly and keep free for running

C.secure more turns to hold the line against any strain，then clear the area

D.surge the line so that it maintains a strain without parting

下列关于轨道说法错误的有（）。

A.轨道的两条钢轨的接头位置相互错开称为错接式，接头的相对错距最小为1m

B.异型轨道长度大于50m为杂拌道

C.浮离是指轨枕两端或一端虚悬的现象

D.空吊板是指轨枕与轨底面不贴合的缺陷