System Analysis and Design
421. Objects selected to model a system
- must be essential for functioning of the system
- must have all attributes which are invariant during operations of a system
- must have attributes relevant for performing services of object
- must be able to perform assigned services
- i, ii, iii
- ii, iii, iv
- i, iii, iv
- i, ii, iii, iv
Correct answer: (C)
i, iii, iv
422. A subsystem of a complex system
- should be reusable in other complex system
- must not be able to inherit the properties of other subsystems
- must have clearly specified responsibilities
- must know the stimuli to which it should respond
- i, ii, iii
- ii, iii, iv
- i, iii, iv
- i, ii, iv
Correct answer: (C)
i, iii, iv
423. An instance of an object is created by a
- query operation
- update operation
- constructor operation
- open operation
Correct answer: (C)
constructor operation
424. By polymorphism in object-oriented modelling we mean
- the ability to manipulate objects of different distinct classes
- the ability to manipulate objects of different distinct classes knowing only their common properties
- use of polymorphic operations
- use of similar operations to do similar things
Correct answer: (B)
the ability to manipulate objects of different distinct classes knowing only their common properties
425. All objects have
- attributes
- states
- a set of operations
- a unique identity
- i, ii, iii
- ii, iii, iv
- i, iii, iv
- i, ii, iii, iv
Correct answer: (D)
i, ii, iii, iv
426. By encapsulation in object-oriented modelling we mean
- encapsulating data and programs
- hiding attributes of an object from users
- hiding operations on object from users
- hiding implementation details of methods from users of objects
Correct answer: (D)
hiding implementation details of methods from users of objects
427. An object is selected for modelling a system provided
- its attributes are invariant during operation of the system
- its attributes change during operation of the system
- it has numerous attributes
- it has no attributes relevant to the system
Correct answer: (B)
its attributes change during operation of the system
428. An update operation in an object instance
- updates the class
- has no side effects
- deletes an instance
- alters values of attribute(s) of an object instance
Correct answer: (D)
alters values of attribute(s) of an object instance
429. Encapsulation in object-oriented modelling is useful as
- it allows improving methods of an object independent of other parts of system
- it hides implementation details of methods
- it allows easy designing
- encapsulates attributes and operations of object
Correct answer: (A)
it allows improving methods of an object independent of other parts of system
430. A polymorphic operation
- has same name
- has same name but uses different methods depending on class
- uses different methods to perform on the same class
- uses polymorphic method
Correct answer: (B)
has same name but uses different methods depending on class