Ravi, like many project (1) ,had studied the waterfall model of software development as the primary software life-cycle (2) . He was all set to use it for an upcoming project, his first assignment. However, Ravi found that the waterfall model could not be used because the customer wanted the software delivered in stages, something. that implied that the system had to be delivered and built in (3) and not as (4). The situation in many other projects is not very different. The real world rarely presents a problem in which a standard process, or the process used in a previous project, is the best choice. To be the most suitable, an existing process must be. (5)to the new problem.A development process, even after tailoring, generally cannot handle change requests. To accommodate change requests without losing control of the project, you must supplement the development process with a requirement change management process.
空白（4）处应选择（）
A.parts
B.modules
C.software
D.awhole
参考答案：D
解析：像很多项目经理一样，Ravi已经把瀑布模型作为软件开发的首选生命周期过程。他已经打算将瀑布模型用于下一个项目中，通常也是首要任务。然而，Ravi发现瀑布模型已经不能使用在这个项目上了，因为顾客想按阶段提交软件，也就意味着系统必须按部分完成和提交而不是一次全部完成和提交。这种情况在其他许多项目中都存在。现实世界中很少以一种标准化过程来呈现问题的，也就是说很少能够重用以前的项目开发过程，虽然这是一种最好的选择。最合适的方法就是修改已经存在的开发过程以适应新问题。一般情况下，一个开发过程即使经过修改也不能处理新的需要。为了适应新的需求，同时也不至于失去项目控制，必须要增加开发步骤以适应改变的需求。