Which of the following statements is TRUE regarding lashing requirements to secure vehicles aboard Ro-Ro vessels?（）

A.It is imperative that the securing of cargo on flats and trailers and in containers be adequate for both road and sea motions
B.The movements experienced by road borne cargo differ significantly from the roll and sway movements of a ship at sea
C.It is necessary for adequate number and strength of securing points on the vehicles themselves in order that lashings may be properly and safely utilized.
D.All the above

A.The securing of cargo on flats and trailers and in containers must be adequate to withstand both road and sea motions
B.The generally recommended lash angle cannot be greater than 45 degrees relative to the deck inany direction
C.It is necessary for an adequate number of securing points on the vehicles themselves in order that lashings may be properly and safely utilized
D.All the above

A.Start ventilation，lower the ramp，notify engine room
B.Lower the ramp，start ventilation，notify engine room
C.Notify engine room，lower the ramp，start ventilation
D.Start ventilation，notify engine room，lower the ramp