The purpose of the requirements definition phase is to produce a clear, complete, consistent, and testable (6) 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 (7) that it must meet. The starting point is usually a set of high-level requirements from the (8) that describe the project or problem.

In either case, the requirements definition team formulates an overall concept for the system and then defines (9) 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 (10) 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.

9（）

A.rules 

B.principles 

C.scenarios 

D.scenes

男，57岁。3月来腹胀、水肿，1周来加重伴腹痛。20年前曾发现HBsAg（+）。查体：可见肝掌及蜘蛛痣。蛙状腹，肝未及，脾肋下4cm，全腹压痛，无明显反跳痛，移动性浊音阳性。化验：血清蛋白24g/L，血球蛋白31g/L，血钾3.8mmol/L，血钠136mmol/L，血氯98mmol/L。

该患者最必要的检查是（）

A.腹水常规+细菌培养

B.尿常规及尿钠检测

C.腹部B超检查

D.腹部CT检查

E.胃镜检查