Due to a constAntly ______ environment， a poor understanding of the user’s needs and preferences，as well as a ______ of willingness to modify ______ organizational structures and decision models，the full economic potential of Web Information Systems(WIS) has not been realized by now. The data object types of the ______ meta model，the Extended World Wide Web Design Technique(eW3DT)，provide hypertext designers ______ a conceptual，user-centric framework and graphical notation for the construction of both，______ and customized models， during the software development ______ of commercial WIS. A reference model as a normative concept represents an abstraction of a ______ company，its functional units， or its(Web) Information System and is intended to streamline the design and implementation of complex applications at ______costs. As precondition for pursuing a partial globalization strategy，eW3DT ______ between technical and content-specific responsibilities for designing， implementing， and maintaining WIS.

A．Existing

B．the

C．fact

D．company

在丁苯橡胶生产中使用高分子凝聚剂有何优点？