（）analysis emphasizes the drawing of pictorial system models to document andvalidate both existing and/or proposed systems. Ultimately, the system models become the（）for designing and constructing an improved system. （）is such a technique. Theemphasis in this technique is process-centered. Systems analysts draw a series of processmodels called （）. （）is another such technique that integrates data and processconcerns into constructs called objects.
Systems analysts draw a series of processmodels called （）
A．PERT
B．DFD
C．ERD
D．UML
