(31) analysis emphasizes the drawing of p
题型：单项选择题
问题：
(31) analysis emphasizes the drawing of pictorial system models to document and validate both existing and/or proposed systems. Ultimately, the system models become the (32) for designing and constructing an improved system. (33) is such a technique. The emphasis in this technique is process-centered. Systems analysts draw a series of process models called (34) . (35) is another such technique that integrates data and process concerns into constructs called objects.
A．PERT
B．DFD
C．ERD
D．UML
