《一个都不能少》是一部______。

A．纪录片

B．纪实片

C．故事片

D．剧情片

What is the purpose of tricing pendants?（）

A.They have the same function as frapping line

B.They are safety lines for personnel inside the lifeboat

C.They slow the descent of the lifeboat

D.They hold the lifeboat alongside the embarkation deck