System analysis is traditionally done top-down using structured analysis based on (1) ．Object-oriented analysis focuses on creation of models．The three types of the analysis model are (2) ．There are two substages of object-oriented analysis． (3) focuses on real-world things whose semantics the application captures．The object constructed in the requirement analysis shows the (4) of the real-world system and organizes it into workable pieces． (5) addresses the computer aspects ofthe application that are visible to users．The objects are those which can be expected to vary from time to time quite rapidly．

4（）

A．static structure

B．system components

C．data flows

D．program procedures

科学家发现，人体中的高密度脂蛋白(HDL)对心脏病有预防作用。每天吸烟超过20支者，体内HDL的含量明显下降。如停止吸烟，含量就会增加。HDL含量最高的是瘦子，最低的是胖子，男孩在达到十几岁时，HDI。含量下降，女孩则相反。老年妇女的HDL含量高于老年男性。 由上可以推出( )

A．与女孩相比，男孩容易患心脏病

B．男性吸烟者患心脏病的概率高于女性

C．男性年岁越大，患心脏病概率越高

D．长的瘦的老年男性患心脏病概率低于长的胖的老年女性