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Correct OPTION is (b) Allows CLIENT to modify/write the private members

The best EXPLANATION: The client can have rights to access a file and write something to it. This is mandatory to keep the private data updated. Also it is an ADVANTAGE over the use of hidden CLASS members.

Correct answer is (d) To make private data accessible to the client

Explanation: The private data of a class is usually not accessible. But the data can be accessed by the USER using ACCESSOR FUNCTIONS. These functions ALLOWS the user to get the data stored as private in a class.

Correct choice is (B) To model real world objects

The best EXPLANATION: The primitive classes are not sufficient for the programming complex algorithms. Some USER defined classes are required to represent a real world object and to DEFINE a blueprint of what the class should actually contain. The user defined classes are as per the requirements and NEED of user.

Correct OPTION is (d) Code reusability, efficiency and readability

To EXPLAIN I would say: The code is reusable as the FUNCTIONS which are already WRITTEN, can be used anytime required. The code becomes easier to read. Also, the code is efficient as there is no need to assign any external code.

Right choice is (c) PROVIDE predefined data and FUNCTIONS

Best explanation: The data that is constant or is always the same initially for use can be PROVIDED by some inbuilt classes. The functions that are mostly USED are also provided by the inbuilt classes. The data and functions can be used by INCLUDING the corresponding header file or library.

Right OPTION is (c) To group the most similar data and OPERATIONS

The explanation: The classes would be more suitable to use in case where we need to group the most similar data and operations. The data can be REPRESENTED as data members of class and operations as member functions of class. This is indirectly ENCAPSULATION feature.

The correct choice is (c) Blueprint

To explain: The class is an OVERVIEW for an OBJECT. It contains the basic details MAP of data that an object will contain. An object is INDEPENDENT representation of class.

Right choice is (a) OBJECT orientation

The best explanation: Thee use of classes feature the object oriented programming. The OOP CONCEPT can be IMPLEMENTED by using class and their OBJECTS. Procedures orientation is not a feature of OOP.

The correct option is (c) Functions can also be encapsulated

The BEST explanation: The functions are also made easy to be encapsulated INSIDE a class. In structures, only the data members were allowed to be encapsulated. HENCE classes can represent an entity in a better WAY.

The CORRECT CHOICE is (d) Base

Best explanation: The base CLASSES are the most abstracted part of INFORMATION. A base class having many other derived classes would have a bigger overview of all the other derived classes. Hence the base classes have the most abstract information.

Right choice is (a) Define a class to store details of each employee

Easy explanation - A single class can be defined that REPRESENTS a single employee of a company. The SPECIFIC type of FUNCTIONS that can be applied to specific employees can be put into ANOTHER class that is derived from the EXISTING class.

The correct option is (b) Define a public function that RETURNS values of two data MEMBERS

Easy explanation - The best choice would be to define a public member function that returns the values of two data members of the class. This WAY we can implement any operation on those data members. Also there won’t be any need to MODIFY the program and to add NEW functions for each new operation.

The CORRECT choice is (a) Class

Easy explanation - A class can be used to GROUP all the BRANDS of cars. The Different brands may have different properties but all will have some common properties like number of wheels and doors, accessories etc. All of those properties can be grouped into a SINGLE class REPRESENTING all the cars.

Correct choice is (b) Encapsulation

For explanation: The classes are MADE to encapsulate the DATA and properties that are most similar and can be grouped TOGETHER inside a SINGLE class. This single class can represent all of those features by creating its instances.

The correct option is (d) PRIVATE INHERITANCE

Explanation: The private members of a class can NEVER be derived to another class. When a class derives another class using private inheritance, all the members become private members of the derived class. Hence these member won’t be AVAILABLE for further inheritance.

Correct option is (d) As many as required

The EXPLANATION: When a CLASS is to be derived from another derived class, the derived class behaves as a normal base class hence there are no RESTRICTION on how many class can be derived from a derived class. The derived class again behaves as a normal SUPERCLASS.

Correct choice is (B) Must become another ABSTRACT CLASS or define

The explanation: The function must be defined in the PROGRAM which are not defined in the base class. Hence the class must be defined as abstract of implement the function DEFINITION in it.

Right answer is (c) CLASS C

The best EXPLANATION: The ABSTRACTION level of class C will be maximum. This is because the parent class have higher level of abstraction. Hence the parent of all other class will have maximum level of abstraction.

The correct option is (a) Friend function of derived class can access non-private members of base class

To EXPLAIN I would say: The friend function of a class can access the non-private members of base class. The reason behind is that the members of base class GETS derived into the derived class and hence BECOME members of derived class too. Hence a friend function can access all of those.

The correct option is (d) As many are required

Best EXPLANATION: There is no RESTRICTION on how many classes can INHERIT a SINGLE base class. Hence there can be as many DERIVED classes as required in a program from a single base class.

The correct choice is (c) 3

Best EXPLANATION: There are three types of inheritance possible. PRIVATE inheritance, protected inheritance, and public inheritance. The inheritance defines the ACCESS specifier to be used with the INHERITED members in the derived CLASS.

Right choice is (d) All except PRIVATE

To explain I would SAY: There is no restriction for a DERIVED CLASS to access the members of the base class until and unless the members are private. Private member are declared so that those members are not accessible OUTSIDE the class.

Right CHOICE is (b) 2

The EXPLANATION is: If there is a DERIVED class in a program, there must be at least 2 CLASSES in that program. One is a base class and ANOTHER derived class. Hence at least 2 classes must be there.

Correct choice is (C) All the members except private members

To explain: The class inheriting another class, inherits all the data members and MEMBER functions that are not private. This is done to ENSURE the SECURITY features with maximum FLEXIBILITY.

Correct answer is (B) A CLASS which INHERITS one or more classes

The best I can explain: Any class which inherits one or more classes is a DERIVED class. The only condition is it MUST inherit at least one class in order to be called as a derived class.

The correct CHOICE is (b) False

Explanation: The base class can be ADDED with new members WITHOUT AFFECTING the subclasses. This is because the subclasses may GET some more features inherited but it won’t use them. But the base class will be able to use the new members as would be required.

Correct option is (d) As many as required

To explain I WOULD say: This is because C++ allows multiple INHERITANCE. A DERIVED CLASS can have more than ONE base class and hence can derive all of their features.

The correct CHOICE is (d) Multi-level

The best explanation: If a base class is inherited from another class, SINGLE inheritance is SHOWN. But when ONE more class inherits the derived class, this becomes a multi-level inheritance.

The correct option is (a) Yes, always

Explanation: If the FUNCTION is defined in the base class, it can always be called from the CONSTRUCTOR of its derived class. Since the CONSTRUCTORS are not PRIVATE, they can be accessed in derived class even if those are PROTECTED.

Correct choice is (a) Before

The best I can explain: When the BASE class object is CREATED, its constructor will be called for sure. But if a derived class constructor is called, FIRST base class constructor is called and then derived class constructor is TAKEN into consideration.

Right OPTION is (B) False

Explanation: When a class have more than one nested classes, it is known as enclosing class. It can’t be called as parent or BASE class SINCE there is no inheritance INVOLVED.

Right answer is (B) Private

The explanation: The private members can be accessed only INSIDE the base CLASS. If the class is derived by other classes. Those members will not be ACCESSIBLE. This concept of OOP is made to make the members more secure.

Right ANSWER is (d) Nothing

Easy EXPLANATION - EVEN a class that doesn’t have any members can be a BASE class. It is not mandatory to have any member or ATTRIBUTE in base class.

The correct answer is (d) Hierarchical

For explanation: When more than one classes are being DERIVED from a single PARENT class, the INHERITANCE is KNOWN as hierarchical inheritance. This is usually USEFUL when the base class is higher abstraction of its derived classes.

Right option is (c) Make a class DERIVE from it

Easy explanation - MAKING another class derive from it will make that class as base class. It is not necessary that we have to write DIFFERENT code for it. If at least one class DERIVES that class, it becomes the base class for the new class.

Right option is (a) 1

Explanation: In java, multiple inheritance is not SUPPORTED, which LEADS to the FACT that a class can have only 1 parent class if inheritance is used. Only if interfaces are used then the class can implement more than one base class.

Right choice is (a) Base

To explain I would say: Every ABSTRACT CLASS is a base class. It must be so, because the FUNCTIONS which are not defined INSIDE the abstract class, must be defined in the derived classes. HENCE it becomes a base class.

Right option is (C) Super

Explanation: A class which is being DERIVED by other classes, is CALLED as super class. This concept is clearly USED in java as we call the functions of a base class by using the keyword super as required.

Right option is (b) False

To explain I would say: There is no mandatory CONDITION to have static members INSIDE TEMPLATE CLASS. Not only template, it is not mandatory to have static members ANYWHERE. We can use them as required in the code.

Right OPTION is (d) As MANY as required

Best explanation: There is no restriction on the number of types to be USED for making the class GENERIC. There can be any number of generic types with a single class. Hence giving flexibility to code with all the data types.

Correct CHOICE is (b) 8-bit CHARACTER and wide characters

The best explanation: The I/O specialization is made with wide character and 8-bit characters. Wide characters are used to STORE the characters that might take more than 1 byte of space in memory or any SIZE that is DIFFERENT from the one that the machine is using.

Right ANSWER is (c) WITHOUT full specification of the data on which

The BEST I can explain: The template classes can ACCEPT all types of data types. There is no need to specify the data on which the class has to operate. Hence it gives US flexibility to code without worrying about the type of data that might be used in the code.

Correct choice is (c) Code REUSABILITY

Explanation: The code reusability is the feature that becomes more powerful with the USE of template CLASSES. You can generate a single code that can be used in variety of PROGRAMMING SITUATIONS.