（）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.

（）is another such technique that integrates data

A．Structured analysis

B．Information Engineering

C．Discovery Prototyping

D．Object-Oriented analysis

甲将所持有的A公司债券交付乙，作为向乙借款的质押物。双方签订了书面质押合同，但未在债券上背书“质押”字样。借款到期后甲未还款。甲的另一债权人丙向法院申请执行上述债券。下列说法哪一个是正确的( )

A．质押合同无效

B．质押合同自签订书面质押合同之日起生效

C．乙对该债券不享有质权

D．乙以债券已出质对抗丙的执行申请，不能得到法院的支持