Which operation should be done when launching an inflatable liferaft by hand?（）

A.Open the liferaft casing

B.Turn the valve on the CO₂ cylinder to start inflation

C.Make sure the operating cord is secured to the vessel before throwing it over the side

D.After inflation，detach operating cord from liferaft

控制工作最基本的目的是（）。

A、保证原有目标的实现

B、有所创新

C、防止问题的发生

D、打破现状