What could be a result of insufficient lubrication of lifeboat winches and davits?（）

A.Moisture accumulation in winch motor damaging the electrical wiring

B.Freezing of gears in cold weather

C.Corroding of sheaves on the davits so they will not rotate

D.All of the above

数据库管理系统中的安全控制模块属于

A．数据库定义程序模块

B．数据库操纵程序模块

C．数据库运行管理程序模块

D．数据库组织、存储和管理程序模块