The purpose of the requirements definition phase is to produce a clear, complete, consistent, and testable （） of the technical requirements for the software product. During the requirements definition phase, the requirements definition team uses an iterative process to expand a broad statement of the system requirements into a complete and detailed specification of each function that the software must perform and each （） that it must meet. The starting point is usually a set of high-level requirements from the （） that describe the project or problem. In either case, the requirements definition team formulates an overall concept for the system and then defines （） showing how the system will be operated, publishes the system and operations concept document, and conducts a system concept review(SCR). Following the SCR, the team derives （） requirements for the system from the high level requirements and the system and operations concept. Using structured or object-oriented analysis, the team specifies the software functions and algorithms needed to satisfy each detailed requirement.

Following the SCR, the team derives（）requirements for the system from the high level requirements and the system and operations concept.

A．detailed

B．outlined

C．total

D．complete

属于影响健康教育效果评价的失访因素是（）。

A.颁布新卫生政策

B.测试者的观察偏倚

C.调查人员技术更加熟

D.因搬迁不能对居民进行随访

E.项目地区发生自然灾害