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回答题：Microsoft's COM is a software __（66）__ that allows applications to be built from binary software components. COM is the underlying architecture that forms the foundation for higher-level software services, like those provided by OLE. COM defines a binary standard for function calling between components, a way for components to dynamically discover the interfaces implemented by other components, and a mechanism to identify components and their interfaces uniquely. OLE is a compound __（67）__ standard developed by Microsoft. OLE makes it possible to create __（68）__ with one application and link or embed them in a second application. Embedded objects retain their original format and __（69）__ to the application that created them. Support for OLE is built into the Windows and MacOS Operating Systems. A __（70）__ compound document standard developed mainly by Apple and IBM is called OpenDoc.（66） A．architecture
B．protocol
C．procedure
D．structure
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