2003年我国开始实施振兴东北老工业基地计划。根据国民经济建设的第一个五年计划可知，东北地区是[ ]

A．轻工业基地    

B．重工业基地    

C．军工产品基地    

D．日用产品基地

The software architecture of a program or computing system is the structure or structures of the system, which comprise software______, the externally ______ properties of those components, and the relationships between them. The architecture is not the operational software. Rather, it is a ______ that enables a so, ware engineer to: analyze the ______ of the design in meeting its stated requirements, consider architectural alternatives at a stage when making design changes is still relatively easy, and reduce the ______ associated with the construction of the software.

A．visible
B．reliable
C．secure
D．robust