67.A management domain typically contains a large amount of management information. Each individual item of( )information is an instance of a managed object type. The definition of a related set of managed ( )types is contained in a Management Information Base (MIB)module. Many such MIB modules are defined. For each managed object type it describes, a MIB ( ) defines not only the semantics and syntax of that managed object type, but also the method of identifying an individual instance so that multiple ( ) of the same managed object type can be distinguished. Typically, there are many instances of each managed object ( ) within a management domain。