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Right answer is (a) Data members

The best explanation: The variables inside a class are termed data members of the class. It is not a mandatory RULE but variables are USED to refer to usual variables used in functions or globally. The term is given because the VALUES stored in those variables represent some KIND of data related to class.

The CORRECT choice is (b) Can be initialized only with help of constructors

The EXPLANATION: The data members are not property of class, those are property of the instances of the class. And the memory for the data members are not RESERVED until a CONSTRUCTOR is called. HENCE we use constructors for their initialization after the memory is reserved.

The CORRECT choice is (d) Static data MEMBERS are DEFINED outside class, not in constructor

The best explanation: Static members are not property of instances of classes. Those are shared by all the object of classes. HENCE those are defined outside the constructor, so as to make them COMMON for all the objects.

Correct option is (a) The STRUCTURE must have been defined before class.

The EXPLANATION is: The structure must have been defined prior to its use. If the structure is not defined, then the memory space will not be allocated for its MEMBERS. This LEADS to undefined use of new data TYPES.

Right answer is (d) As many as REQUIRED

The best I can EXPLAIN: Any CLASS can have as many data members as required. The only RESTRICTION that may arise is when there is not enough memory space. This gives FLEXIBILITY to define a class with best properties possible.

Right CHOICE is (c) Dot or arrow as required

The EXPLANATION: The DATA members can never be called directly. Dot operator is USED to access the members with help of object of class. Arrow is USUALLY used if pointers are used.

The CORRECT choice is (a) Return the address of the private DATA member using a member function

The BEST explanation: We can CALL a public member function and return the address of any private data member. Though the pointer being returned must be defined INSIDE class itself. And the returned address can be stored in a pointer.

The correct answer is (a) STATIC data MEMBERS

To explain: The static member functions can only access static data members. This is because the static member function can’t WORK with the properties that change object to object. It is mandatory that only the common properties of all the objects be used. And only static data members are common to all as those are PROPERTY of class.

Right choice is (b) False

The explanation is: The DATA members in a class can never refer to own class TYPE. This is not POSSIBLE because the data members should have some memory allocated for its object before the self-reference is used, but class MUST CALL constructor for that. Hence not possible.

Right OPTION is (b) const

Easy explanation - The keyword const can be used ANYWHERE to make the VARIABLE have same value all the time. This restriction is made to use the same value whenever required. Also, this can restrict accidental changes.

Correct answer is (b) Protected

To explain I WOULD say: Static MEMBERS inheritance ALSO depends on the TYPE of specifier they have. Only the protected members can be inherited but remain private to class. If static members are defined in private access, they won’t be allowed for inheritance.

The correct option is (b) False

Best explanation: This is a wrong STATEMENT. As only the data defined inside CLASS is considered as its member. But even if a variable is PASSED by reference it would be the same variable that is outside the class. HENCE it can’t be considered class member.

The CORRECT answer is (c) abstract a;

To explain: The abstract KEYWORD in the declaration of data members is not allowed. This is because the abstract keyword FEATURES can’t be used with the data members of the class. We can have all other SYNTAX given, but not abstract.

Correct CHOICE is (d) 5

Easy explanation - There are 5 TYPES of member functions that are generally provided in C++. NAMELY, SIMPLE, static, const, inline and friend member functions. Member functions are SPECIFIC to classes.

Correct choice is (d) USING DOT, arrow or using scope RESOLUTION operator with class name

The best I can explain: The member functions can be called using only the dot operator or the arrow operator. But the static members can be called using directly the class name FOLLOWED by the scope resolution operator and static member function name. This is useful when you don’t have any object to call the member.

The CORRECT option is (b) Member FUNCTIONS WHOSE definition is expanded in place of its call

Easy EXPLANATION - The member functions whose definition is expanded at the call, and no jump to function and return happened, are TERMED as inline functions. This is used to make the program faster and more efficient.

Right option is (a) Compile TIME ERROR

The best I can explain: There must be specific memory space allocated for the data members before the static member functions USES them. But the space is not reserved if OBJECT is not declared. HENCE only if static members are not used, it leads to compile time error.

Right CHOICE is (c) Doesn’t CONTAIN “this” pointer

The best EXPLANATION: The STATIC member functions doesn’t contain “this” pointer. Static member functions can’t be defined as const or VOLATILE also. These are restrictions on static member functions.

The correct ANSWER is (d) USED directly or with this POINTER

The EXPLANATION is: The members of a class can be used directly inside a member FUNCTION. We can use this pointer when there is a conflict between data members of class and arguments/local function variable names.

The correct answer is (C) MUST be non-static member and should not be FRIEND of class

To explain I would SAY: For overloading those operators for a class, the class must use non-static member function so that doesn’t remain common to all the objects, and each OBJECT can use it independently. The friend functions is also restricted so as to keep the security of data.

The correct answer is (a) It should not contain any body and DEFINED by subclasses

Explanation: The VIRTUAL functions are defined USING virtual keyword. These are made in order to make all the CLASSES to define them as the class gets inherited. INCREASES code understanding.

Correct answer is (b) Automatically GENERIC

Explanation: When generic type is used in a CLASS, the functions are automatically generic. This is so because the functions would use the same type as defined to MAKE the class generic. The functions will get to know the type of DATA as soon as the generic class is used. It’s INBUILT feature.

Right OPTION is (a) Access all the members of the class

To EXPLAIN: The MEMBER functions has access to all the members of the class. Whenever data members of a class, which might be private, have to be MODIFIED, we make use of these member functions. This is more secure way to manipulate data.

Correct option is (a) Call other member functions

For EXPLANATION: We can call ONE function inside another function to access some data of class. A public member function can be USED to call a PRIVATE member function which directly manipulates the private data of class.

Right choice is (d) CONSTRUCTOR and destructor

For EXPLANATION: All the member FUNCTIONS work same as normal functions with syntax. But the constructor and destructor are also CONSIDERED as member functions of a class, and they never have any data type.

Right choice is (c) ACCESS PUBLIC members of SUBCLASS

To explain: A member function of a class can only have the access to the members of its own class and parent classes if inheritance used. Otherwise a member function can never access the members of a subclass. Accessing static members of a class is possible by NORMAL and static member functions.

The correct option is (b) CLASSES DECLARED inside a function

The EXPLANATION: The classes declared inside a package are available to all the functions and classes, HENCE can’t be called local. This is somewhat similar concept that we use to denote variables of a function. The classes declared inside functions will be local to them.

The correct choice is (c) Defined INSIDE the CLASS body

The EXPLANATION: There is a restriction on where the MEMBER functions of the local class should be define. Those MUST be defined inside the class body only. This is to reduce the ambiguity and complexity of program.

Correct ANSWER is (a) Static and extern

Easy explanation - The local classes have this feature to ACCESS the static and extern variables of the function in which those are DEFINED. This feature is available since these type of data are common to the program and is CREATED only one time. Run time CREATION and destruction of these variables is not done. The only restriction that may apply is those members must be constants.

The correct ANSWER is (a) True

Easiest explanation - This is a little TRICKY part with local classes. THOUGH the local class can’t access the general variables of the function but can access the types that are DEFINED INSIDE the function. This is because the whole definition of that type would be existing inside the class.

The correct answer is (d) No, not possible anyway

The explanation is: No, the STATIC variables can’t be declared inside a local class. This is because each time the function is CALLED, all the variables get created again and are DESTROYED as soon as the function is RETURNED. This WOULD have been possible id the static variable was of function.

The correct ANSWER is (a) YES, since local

For EXPLANATION: The local classes can have same name if they belong to different functions. The classes would be local to those specific functions and hence can have same name. This is same as that of local variables CONCEPT.

Correct CHOICE is (b) WITHIN the function

To explain I would say: The SCOPE of a local class is limited only within the function definition. The function can use the class as usual as local VARIABLES. The class gets destroyed as soon as the function is returned.

The correct OPTION is (c) Helps to add extra functionality to a function

Easy explanation - The closest answer is to add more functionalities to a function or to MAKE some specific FUNCTIONS to be generic. Adding more members to a function can be DONE directly but to add some special functionality that are encapsulated, can be done USING local classes.

Correct option is (a) CLASS inside a class

To EXPLAIN: If a class is DEFINED inside another class, the inner class is termed as nested class. The inner class is local to the enclosing class. SCOPE MATTERS a lot here.

Correct CHOICE is (B) INHERITANCE

The best explanation: USING inheritance we can have the security of the class being inherited. The subclass can access the members of parent class. And have more feature than a NESTED class being used.

Correct CHOICE is (a) 2

The EXPLANATION: The nested classes are divided into two MAIN categories. Namely, Static and non-static. The categories define how the classes can be used INSIDE another CLASS.

The correct option is (d) All the MEMBERS

The explanation is: The non-static nested class can ACCESS all the members of the enclosing class. All the data members and MEMBER functions can be ACCESSED from the nested class. Even if the members are private, they can be accessed.

The correct choice is (d) Any other members

Best explanation: The static nested class doesn’t have ACCESS to any other members of the ENCLOSING class. This is a rule that is made to ensure that only the data which can be COMMON to all the object is being ACCESSED by the static nested class.

Correct answer is (d) PUBLIC, PROTECTED, PRIVATE or PACKAGE private

The best I can explain: The nested class can be declared with any specifier, unlike the outer classes which can only be declared public or package private. This is flexibility given for the nested class being a member of enclosing class.