Traditional structured analysis techniques focus upon the flow of(71)within a system. Object - oriented analysis emphasizes the building of real - world models. It examines requirements from the perspective of the classes and objects found in the vocabulary of the(72)domain.

Traditional system design method emphasizes the proper and effective structure of a complex system. Object -oriented design method encompasses the process of object -oriented decomposition and a(73)for depicting both logical and physical as well as static and dynamic models of the system under design.

Object - oriented programming is a method of implementation in which programs are organized as cooperative collections of objects, each of which represents an(74)of some class, and whose classes are all members of a hierarchy of classes united via(75)relationships.

A．control

B．program

C．data

D．reference