广播消息与广播通讯相比较，最大的差别在

A．思想性

B．时效性

C．接近性

D．趣味性

A flooded lifeboat on board a vessel would adversely affect the vessel’s stability by（）.

A.increasing the righting moment

B.decreasing the vessel's displacement

C.increasing the reserve buoyancy

D.shifting the CG (center of gravity) off center