OOAD MCQs and Answers With Explanation – Object-Oriented Analysis and Design (OOAD) is a popular software engineering approach that emphasizes the use of objects to model and design complex systems. The principles of OOAD help developers create software that is easier to maintain, more scalable, and more efficient. These Top 45 OOAD Multiple Choice Questions help you understand the OOAD better and also you can take reference from these Object Oriented Analysis and Design MCQ with Answers to prepare for the interview or placement exam.
Object Oriented Analysis and Design MCQs
To assess your understanding of OOAD, you can take an OOAD Quiz that covers different topics such as UML diagrams, design patterns, and the principles of object-oriented programming. These MCQs can help you gauge your knowledge and improve your understanding of OOAD concepts, enabling you to become a better software developer.
| Join Telegram |  |
| Join Whatsapp Groups |  |
OOAD Multiple Choice Questions
| Name | OOAD |
| Exam Type | MCQ (Multiple Choice Questions) |
| Category | Technical Quiz |
| Mode of Quiz | Online |
Top 45 Object Oriented Analysis and Design MCQ Questions
1. What does OOAD stand for?
a) Object Oriented Analysis and Design
b) Online Object Analysis and Design
c) Objective Oriented Analysis and Documentation
d) Objective Oriented Algorithm Design
Answer: a) Object Oriented Analysis and Design
Explanation: OOAD is an acronym for Object Oriented Analysis and Design. It is a software engineering methodology used to model and design software systems using object-oriented concepts.
2. What is the purpose of object-oriented analysis?
a) To identify the objects and their attributes
b) To define the system requirements
c) To model the system using object-oriented concepts
d) All of the above
Answer: d) All of the above
Explanation: Object-oriented analysis is the process of identifying objects and their attributes, defining system requirements, and modeling the system using object-oriented concepts.
3. What is the purpose of object-oriented design?
a) To identify the objects and their attributes
b) To define the system requirements
c) To model the system using object-oriented concepts
d) To develop the code for the system
Answer: d) To develop the code for the system
Explanation: Object-oriented design is the process of developing the code for the system based on the model developed during object-oriented analysis.
4. What is encapsulation?
a) Hiding the complexity of the object from the user
b) Hiding the object from the user
c) Hiding the methods of the object from the user
d) None of the above
Answer: a) Hiding the complexity of the object from the user
Explanation: Encapsulation is a fundamental concept in object-oriented programming that involves hiding the complexity of an object from the user by restricting access to its internal workings.
5. What is inheritance?
a) The process of creating a new class from an existing class
b) The process of creating an object from a class
c) The process of creating a subclass from a superclass
d) None of the above
Answer: c) The process of creating a subclass from a superclass
Explanation: Inheritance is the process of creating a new subclass from an existing superclass. The subclass inherits all the properties and behaviors of the superclass.
6. What is polymorphism?
a) The ability of an object to take on many forms
b) The ability of a method to take on many forms
c) The ability of a class to take on many forms
d) None of the above
Answer: b) The ability of a method to take on many forms
Explanation: Polymorphism is the ability of a method to take on many forms, depending on the context in which it is used.
7. What is a class?
a) A blueprint for creating objects
b) An object
c) A method
d) None of the above
Answer: a) A blueprint for creating objects
Explanation: A class is a blueprint for creating objects. It defines the properties and behaviors of the objects that will be created from it.
8. What is an object?
a) A blueprint for creating classes
b) An instance of a class
c) A method
d) None of the above
Answer: b) An instance of a class
Explanation: An object is an instance of a class. It has the properties and behaviors defined by the class.
9. What is a constructor?
a) A method used to create objects
b) A method used to destroy objects
c) A method used to modify objects
d) None of the above
Answer: a) A method used to create objects
Explanation: A constructor is a special method used to create objects. It is called when an object is created and is used to initialize the object’s properties.
10. What is a method?
a) A method used to create objects
b) A method used to destroy objects
c) A method used to modify objects
d) None of the above
Answer: c) A method used to modify objects
Explanation: A method is a block of code that performs a specific task. It is used to modify the properties and behaviors of an object.
11. What is a superclass?
a) A class that inherits from another class
b) A class from which other classes are derived
c) A class that is used to create objects
d) None of the above
Answer: b) A class from which other classes are derived
Explanation: A superclass is a class from which other classes are derived. It defines the common properties and behaviors that will be inherited by its subclasses.
12. What is a subclass?
a) A class that inherits from another class
b) A class from which other classes are derived
c) A class that is used to create objects
d) None of the above
Answer: a) A class that inherits from another class
Explanation: A subclass is a class that inherits properties and behaviors from a superclass. It can also define its own unique properties and behaviors.
13. What is a UML diagram?
a) A diagram used to model object-oriented software systems
b) A diagram used to model procedural software systems
c) A diagram used to model functional software systems
d) None of the above
Answer: a) A diagram used to model object-oriented software systems
Explanation: UML (Unified Modeling Language) is a visual modeling language used to model object-oriented software systems. It includes various types of diagrams, such as class diagrams, use case diagrams, sequence diagrams, and activity diagrams.
14. What is a use case diagram?
a) A diagram used to model the interactions between users and the system
b) A diagram used to model the classes and their relationships in the system
c) A diagram used to model the flow of activities in the system
d) None of the above
Answer: a) A diagram used to model the interactions between users and the system
Explanation: A use case diagram is a UML diagram used to model the interactions between users and the system. It shows the various use cases (or tasks) that the user can perform and the interactions between the user and the system.
15. What is a class diagram?
a) A diagram used to model the interactions between users and the system
b) A diagram used to model the classes and their relationships in the system
c) A diagram used to model the flow of activities in the system
d) None of the above
Answer: b) A diagram used to model the classes and their relationships in the system
Explanation: A class diagram is a UML diagram used to model the classes and their relationships in the system. It shows the properties and behaviors of the classes, as well as the relationships between the classes.
16. What is a sequence diagram?
a) A diagram used to model the interactions between users and the system
b) A diagram used to model the classes and their relationships in the system
c) A diagram used to model the flow of activities in the system
d) None of the above
Answer: a) A diagram used to model the interactions between users and the system
Explanation: A sequence diagram is a UML diagram used to model the interactions between objects in a system. It shows the sequence of messages exchanged between the objects.
17. What is an activity diagram?
a) A diagram used to model the interactions between users and the system
b) A diagram used to model the classes and their relationships in the system
c) A diagram used to model the flow of activities in the system
d) None
Answer: c) A diagram used to model the flow of activities in the system
Explanation: An activity diagram is a UML diagram used to model the flow of activities in the system. It shows the various activities that are performed in the system and the order in which they are performed.
18. What is abstraction?
a) The process of creating new objects from existing objects
b) The process of creating new classes from existing classes
c) The process of representing essential features of an object without including unnecessary details
d) None of the above
Answer: c) The process of representing essential features of an object without including unnecessary details
Explanation: Abstraction is the process of representing essential features of an object without including unnecessary details. It helps to simplify the complexity of the system and make it easier to understand and maintain.
19. What is a destructor?
a) A method used to create objects
b) A method used to destroy objects
c) A method used to modify objects
d) None of the above
Answer: b) A method used to destroy objects
Explanation: A destructor is a special method used to destroy objects. It is called automatically when an object is no longer needed and is used to free up any resources that were allocated for the object.
20. What is a static method?
a) A method that can be called without creating an object of the class
b) A method that can be called only by objects of the class
c) A method that is used to modify objects
d) None of the above
Answer: a) A method that can be called without creating an object of the class
Explanation: A static method is a method that can be called without creating an object of the class. It is associated with the class rather than with any specific instance of the class.
21. What is a static variable?
a) A variable that can be accessed only by objects of the class
b) A variable that is used to modify objects
c) A variable that is shared by all instances of the class
d) None of the above
Answer: c) A variable that is shared by all instances of the class
Explanation: A static variable is a variable that is shared by all instances of the class. It is associated with the class rather than with any specific instance of the class.
22. What is a final variable?
a) A variable that can be modified after it has been initialized
b) A variable that cannot be modified after it has been initialized
c) A variable that is used to modify objects
d) None of the above
Answer: b) A variable that cannot be modified after it has been initialized
Explanation: A final variable is a variable that cannot be modified after it has been initialized. Once it has been assigned a value, it cannot be changed.
23. What is an abstract class?
a) A class that cannot be instantiated
b) A class that can be instantiated
c) A class that is used to modify objects
d) None of the above
Answer: a) A class that cannot be instantiated
Explanation: An abstract class is a class that cannot be instantiated. It is used as a base class for other classes and provides a common interface for those classes.
24. What is an interface?
a) A class that cannot be instantiated
b) A class that provides a common interface for other classes
c) A class that is used to modify objects
d) None of the above
Answer: b) A class that provides a common interface for other classes
Explanation: An interface is a type that provides a common interface for other classes. It defines a set of methods that other classes can implement.
25. What is a package?
a) A collection of classes and interfaces
b) A collection of variables and methods
c) A collection of objects
d) None of the above
Answer: a) A collection of classes and interfaces
Explanation: A package is a collection of related classes and interfaces. It is used to organize and group related code.
26. What is a use case?
a) A diagram used to model the flow of activities in the system
b) A diagram used to model the interactions between actors and the system
c) A diagram used to model the relationships between classes
d) None of the above
Answer: b) A diagram used to model the interactions between actors and the system
Explanation: A use case is a UML diagram used to model the interactions between actors and the system. It shows the different ways that actors can interact with the system and the system’s response to those interactions.
27. What is an actor in a use case diagram?
a) A class that interacts with the system
b) A person, organization, or system that interacts with the system
c) A method that interacts with the system
d) None of the above
Answer: b) A person, organization, or system that interacts with the system
Explanation: An actor in a use case diagram is a person, organization, or system that interacts with the system. It is represented by a stick figure in the diagram.
28. What is an association in a class diagram?
a) A relationship between classes
b) A relationship between objects
c) A relationship between methods
d) None of the above
Answer: a) A relationship between classes
Explanation: An association in a class diagram is a relationship between classes. It represents that one class is related to another class in some way.
29. What is a multiplicity in an association?
a) The number of objects that can be involved in the relationship
b) The type of relationship between objects
c) The type of relationship between classes
d) None of the above
Answer: a) The number of objects that can be involved in the relationship
Explanation: Multiplicity in an association specifies the number of objects that can be involved in the relationship between classes.
30. What is aggregation in a class diagram?
a) A type of association that represents a “whole-part” relationship
b) A type of association that represents an “is-a” relationship
c) A type of relationship between objects
d) None of the above
Answer: a) A type of association that represents a “whole-part” relationship
Explanation: Aggregation in a class diagram is a type of association that represents a “whole-part” relationship between classes. It indicates that one class is composed of or contains another class.
31. What is composition in a class diagram?
a) A type of association that represents a “whole-part” relationship where the parts cannot exist independently of the whole
b) A type of association that represents an “is-a” relationship
c) A type of relationship between objects
d) None of the above
Answer: a) A type of association that represents a “whole-part” relationship where the parts cannot exist independently of the whole
Explanation: Composition in a class diagram is a type of association that represents a “whole-part” relationship where the parts cannot exist independently of the whole. It indicates that the composite object has ownership and responsibility for the existence and disposal of the parts.
32. What is inheritance in a class diagram?
a) A mechanism for creating new classes from existing classes
b) A type of relationship between objects
c) A type of association that represents a “whole-part” relationship
d) None of the above
Answer: a) A mechanism for creating new classes from existing classes
Explanation: Inheritance in a class diagram is a mechanism for creating new classes from existing classes. It allows a new class to inherit the attributes and methods of an existing class.
33. Which of the following is not a fundamental design principle of object-oriented analysis and design?
a) Encapsulation
b) Inheritance
c) Polymorphism
d) Iteration
Answer: d) Iteration
Explanation: Iteration is not a fundamental design principle of object-oriented analysis and design. It is a programming concept that is used to repeat a set of instructions until a certain condition is met.
34. What is an object diagram?
a) A diagram that represents the interactions between actors and the system
b) A diagram that represents the relationships between classes
c) A diagram that represents the interactions between objects
d) None of the above
Answer: c) A diagram that represents the interactions between objects
Explanation: An object diagram is a diagram that represents the interactions between objects. It shows the objects in a system and how they are related to each other.
35. What is a state machine diagram?
a) A diagram that represents the interactions between actors and the system
b) A diagram that represents the relationships between classes
c) A diagram that represents the different states of an object and the transitions between them
d) None of the above
Answer: c) A diagram that represents the different states of an object and the transitions between them
Explanation: A state machine diagram is a diagram that represents the different states of an object and the transitions between them
36. What is a collaboration diagram?
a) A diagram that represents the interactions between actors and the system
b) A diagram that represents the relationships between classes
c) A diagram that represents the interactions between objects and their relationships
d) None of the above
Answer: c) A diagram that represents the interactions between objects and their relationships
Explanation: A collaboration diagram is a diagram that represents the interactions between objects and their relationships. It shows the objects involved in a particular interaction and the messages that are exchanged between them.
37. What is coupling?
a) The degree to which two classes are related to each other
b) The degree to which two classes are independent of each other
c) The degree to which two classes share a common interface
d) None of the above
Answer: a) The degree to which two classes are related to each other
Explanation: Coupling is the degree to which two classes are related to each other. It measures the extent to which changes in one class affect the other class.
38. What is cohesion?
a) The degree to which two classes are related to each other
b) The degree to which the methods in a class are related to each other
c) The degree to which two classes share a common interface
d) None of the above
Answer: b) The degree to which the methods in a class are related to each other
Explanation: Cohesion is the degree to which the methods in a class are related to each other. It measures the extent to which the methods in a class work together to achieve a single purpose.
39. Which design pattern is used to create objects without specifying the exact class to create?
a) Abstract Factory
b) Builder
c) Factory Method
d) Prototype
Answer: c) Factory Method
Explanation: Factory Method is a creational design pattern that provides an interface for creating objects in a superclass, but allows subclasses to alter the type of objects that will be created. This pattern is used to create objects without specifying the exact class to create.
40. Which design pattern is used to encapsulate a group of individual factories?
a) Abstract Factory
b) Builder
c) Factory Method
d) Prototype
Answer: a) Abstract Factory
Explanation: Abstract Factory is a creational design pattern that provides an interface for creating families of related or dependent objects without specifying their concrete classes. This pattern encapsulates a group of individual factories that have a common theme.
41. Which design pattern is used to separate the construction of a complex object from its representation?
a) Abstract Factory
b) Builder
c) Factory Method
d) Prototype
Answer: b) Builder
Explanation: Builder is a creational design pattern that separates the construction of a complex object from its representation, allowing the same construction process to create different representations. This pattern is used when the process of constructing a complex object is too complex to be contained within a single class.
42. Which design pattern is used to clone an existing object instead of creating a new one?
a) Abstract Factory
b) Builder
c) Factory Method
d) Prototype
Answer: d) Prototype
Explanation: Prototype is a creational design pattern that allows an object to be cloned instead of creating a new one from scratch. This pattern is used when creating an object is expensive or complex, and it is more efficient to clone an existing object.
43. Which design pattern is used to decouple a sender and receiver of a request?
a) Chain of Responsibility
b) Command
c) Interpreter
d) Iterator
Answer: b) Command
Explanation: Command is a behavioral design pattern that decouples a sender and receiver of a request by encapsulating the request as an object. This pattern allows requests to be queued, logged, and otherwise manipulated, and it can support undoable operations.
44. Which design pattern is used to handle requests by chaining multiple objects together?
a) Chain of Responsibility
b) Command
c) Interpreter
d) Iterator
Answer: a) Chain of Responsibility
Explanation: Chain of Responsibility is a behavioral design pattern that handles requests by chaining multiple objects together. Each object in the chain has the ability to handle the request, and can either handle it or pass it on to the next object in the chain.
45. Which design pattern is used to represent a grammar of a language?
a) Chain of Responsibility
b) Command
c) Interpreter
d) Iterator
Answer: c) Interpreter
Explanation: Interpreter is a behavioral design pattern that represents a grammar of a language, and provides a way to interpret sentences in that language. This pattern is used to define a language, and to implement an interpreter for that language.
We hope that these Object Oriented Analysis and Design MCQs have helped you gain knowledge about the OOAD concept. If you’re interested in more technical quizzes in the software field, please follow our website, Freshersnow.