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Correct answer is (c) Method overriding is done with directive override

Best explanation: This is POSSIBLE but only if the method to be overridden is marked as dynamic or virtual. It is inbuilt restriction of programming LANGUAGE. This is done to REDUCE the accidental or unintentional overriding.

Right CHOICE is (a) NON – virtual or STATIC methods can’t be OVERRIDDEN

Easiest explanation - The non-virtual and static methods can’t be overridden in C# language. The restriction is made from the language implicitly. Only the methods that are abstract, virtual or OVERRIDE can be overridden.

Correct answer is (b) C#

To explain I would SAY: The feature of METHOD overriding is not provided in C#. To override the methods, ONE must use override or virtual keywords explicitly. This is done to REMOVE accidental changes in program and unintentional overriding.

The CORRECT ANSWER is (b) Must not be PRIVATE base class

For explanation: If the FUNCTION is private in the base class, derived class won’t be able to access it. When the derived class can’t access the function to be overridden then it won’t be able to override it with any definition.

Correct choice is (c) USING scope resolution operator

To EXPLAIN: Scope resolution operator :: can be USED to access the BASE class method even if overridden. To access those, first base class NAME should be written followed by the scope resolution operator and then the method name.

The correct answer is (d) All the same return type, NAME and parameter list

Explanation: Declaration includes the WHOLE prototype of the FUNCTION. The return type name and the parameter list must be same in order to CONFIRM that the function is same in derived and the base class. And hence can be overridden.

Correct option is (b) The declaration MUST be exactly the same in base and derived class

Best explanation: For a FUNCTION to be over ridden, the declaration must be exactly the same. There must not be any DIFFERENT syntax used. This will ensure that the function to be OVERRIDDEN is only the ONE intended from to be overridden from the derived class.

Right option is (C) Inheritance must be DONE, to use overriding are overridden

Best explanation: The inheritance must be used in order to use function overriding. If inheritance is not used, the functions can only be OVERLOADED. There must be a base class and a derived class to override the function of base class.

The correct choice is (b) delete

Easy EXPLANATION - The delete operator in C++ can be used to FREE the memory and resources held by an object. The function can be called explicitly WHENEVER required. In C++ memory management must be DONE by the programmer. There is no AUTOMATIC memory management in C++.

Correct answer is (d) Garbage collector

To EXPLAIN I would SAY: The garbage collector in JAVA takes care of the memory allocations and their deletions dynamically. When an OBJECT is no more required then the garbage collector deletes the object and free up all the RESOURCES that were held by that object.

The CORRECT choice is (c) Can be static or dynamic

The explanation is: The memory allocation for an OBJECT can be static or dynamic. The static memory allocation is when an object is declared DIRECTLY without USING any function usually. And dynamic allocation is when we use some dynamic allocation function to ALLOCATE memory for data member of an object.

Correct choice is (a) sizeof(objectName)

To explain: The sizeof OPERATOR is used to get the size of an ALREADY created object. This operator MUST constail keyword sizeof(objectName). The output will give the number of bytes acquired by a single object of some class.

The CORRECT choice is (a) Destructor function

To EXPLAIN: The destructor function of the class is called whenever an object GOES out of SCOPE. This is because the destructor set all the resources, acquired by the object, free. This is an implicit WORK of compiler.

Right option is (b) When OBJECT goes out of scope

Best explanation: Whenever an object goes out of scope, the deletion of allocation memory takes place. ACTUALLY the DATA is not deleted, instead the memory SPACE is flagged to be free for further use. Hence whenever an object goes out of scope the object members become useless and hence memory is set free.

The correct answer is (a) new

Explanation: The keyword new can be used to declare an array of objects in java. The syntax must be specified with an object pointer which is assigned with a MEMORY space containing the required NUMBER of object space. EVEN initialization can be done DIRECTLY.

Right OPTION is (d) both malloc() and calloc()

The EXPLANATION: The malloc() function can be used to allocate DYNAMIC memory for objects. Function calloc() can also be USE. These functions differ in the way they allocate memory for objects.

Correct answer is (b) It doesn’t require to be specified with type of data

To explain: The NEW is type safe because we don’t have to specify the type of data that have to be allocated with memory. We can directly USE it with data name. Name of the data doesn’t matter though for type of memory ALLOCATION though.

Correct answer is (C) RAM

The best I can explain: The MEMORY for the objects or any other data is allocated in RAM initially. This is while we run a program all the memory allocation takes place in some RAM SEGMENTS. ARRAYS in heap and local members in stack etc.

The CORRECT OPTION is (a) Actual creation and memory allocation for object MEMBERS

The BEST explanation: The memory allocated for the object members indicates actual creation of the object members. This is known as memory allocation for object.

Right option is (C) Both << and >> operators

The best I can explain: In some cases it is mandatory to use the friend functions for overloading the operators. Here both the << and >> operators must be OVERLOADED using friend function because the LEFT operand is object of some other class and the right operand is usually of some DIFFERENT type.

Right answer is (B) False

Explanation: It is not the case that all the operators can be overloaded using the MEMBER operator overloading. There are some CASES where the operators must be overloaded using the FRIEND function only. The REASON behind is that the left operand should be passed *this pointer, but the left operand in these cases might be object of some other class. Hence can’t be done.

Correct option is (d) Modulus OPERATOR

For explanation: Only the modulus operator among the given OPERATORS can be overloaded using either friend FUNCTION or member function. Other operators must be overloaded using only the member FUNCTIONS.

The correct answer is (a) Assignment operator

Explanation: Only the assignment operator AMONG the options given must be overloaded using the member functions. The assignment operator can’t be overloaded using friend FUNCTION. This is a restriction in the programming languages to make the PROGRAMS more resistant TOWARDS errors.

Correct choice is (c) Left most parameter

To explain I would say: The left operand is PASSED implicitly by the compiler to the member function. But this is DONE, when the compiler adds the CALLING OBJECT as *this to the parameter list. It is ALWAYS added as the left most parameter, i.e. the first parameter of the function.

The correct choice is (b) Two parameters of friend function BECOMES only one PARAMETER of member function

To explain I would say: The friend function would accept two ARGUMENTS if some binary operator is overloaded. When we try to CONVERT that definition to member operator overloading then it becomes only one parameter. The reason behind is that the left operand is passed implicitly while using the member functions.

Right answer is (a) LEFT operand members

To EXPLAIN I would say: This is because the left operand is passed implicitly. It is pointed by *this. This in turn means we can use the direct member NAMES of the OBJECT because those are again converted to a syntax CONTAINING *this pointer implicitly.

Correct answer is (a) CLASSNAME::operator(parameters)

To explain I would say: The CLASS name is followed by the scope resolution operator. This is DONE to specify the class to which the FUNCTION should belong to. Then the KEYWORD operator should be used in order to indicate the operator that is to be overloaded. Then come the parameters list to specify other operands.

Correct choice is (a) Scope resolution OPERATOR

Best explanation: The scope resolution operator can be used followed by the class name. Then the operator keyword with the operator symbol that should be OVERLOADED. This is done to USE member function INSTEAD of FRIEND function.

The CORRECT choice is (d) Other operands are PASSED as FUNCTION arguments

The explanation is: The operands that are USED during overloading expect the left operand, can be passed as function arguments. Those are then referred in function definition with the names specified in the argument list.

Correct CHOICE is (B) The left operand acts as IMPLICIT object represented by *this

The best I can EXPLAIN: The left operand becomes the object that is referred by *this pointer in the member function that will be called while using operator overloading. This is done to point to a specific object on which the overloading will be applied.

The correct option is (a) Overloaded operator MUST be member FUNCTION of the left operand

To explain I would say: The operator to be overloaded must be made the member function of the operand on left side of EXPRESSIONS to be used. This allows the compiler to identify whether the overloading has to be used or not. This rule also reduces the ambiguity in CODE.

Correct choice is (c) EITHER member functions or friend functions can be USED

Easy explanation - The OPERATORS can be OVERLOADED by using the member function or even the friend functions can be used. This is because both of these can access all the data members of a class.

Right choice is (b) inline

To explain: The inline keyword is used to defined the inline MEMBER functions in a class. The functions are IMPLICITLY MADE inline if defined inside the class body, but only if they doesn’t have any complex STATEMENT inside. All functions defined outside the class body must be mentioned with an explicit inline keyword.

Correct ANSWER is (d) Member functions can be defined in any ACCESS SPECIFIER

The best EXPLANATION: The member functions can be defined inside any specifier. There is no restriction. The programmer can APPLY restrictions on its use by specifying the access specifier with the functions.

Correct choice is (b) False

The explanation: There is no restriction on the use of type of MEMBER FUNCTIONS inside a single CLASS. Any type any number of times can be defined inside a class. The member functions can be USED as required.

Right choice is (C) Must be defined outside the class body

The best explanation: The functions DEFINITIONS can be given inside or outside the body of class. If defined inside, general SYNTAX is used. If defined outside then the class name followed by scope RESOLUTION operator and then function name must be given for the DEFINITION.

Correct ANSWER is (c) friend

The best explanation: The keyword friend is provided in PROGRAMMING LANGUAGES to USE it WHENEVER a functions is to be made friend of one class or other. The keyword indicates that the function is capable of new functionalities like accessing private members.

The correct OPTION is (a) void fun() CONST {}

EASY explanation - The general syntax to be followed in ORDER to declare a const function in a class is as in option a. The syntax may vary in different programming languages.

The correct choice is (d) Non-MEMBER FUNCTIONS which have access to all the members (including private) of a class

The best explanation: A non-member function of a class which can access even the private data of a class is a FRIEND function. It is an EXCEPTION on access to private members outside the class. It is sometimes CONSIDERED as a member functions since it has all the access that a member function in general have.

Correct option is (d) Functions defined inside the CLASS or with the KEYWORD inline

Easiest explanation - The functions which are defined with the keyword inline or are defined inside the class are treated to be inline functions. Definitions inside the class are implicitly made inline if none of the COMPLEX statements are used in the definition.

Right option is (C) FUNCTIONS which treat all the data members as constant and doesn’t ALLOW changes

The best I can explain: The CONST member functions are intended to keep the value of all the data members of a class same and doesn’t allow any changes on them. The data members are treated as constant data and any modification inside the const FUNCTION is restricted.

Right choice is (B) CLASSNAME::functionName();

Easy explanation - The syntax in option b must be followed in order to CALL the static functions directly from the MAIN() FUNCTION. That is a predefined syntax. Scope resolution helps to spot the correct function in the correct class.

The correct option is (C) Scope resolution operator

The explanation is: The static MEMBER functions can be accessed directly in the main() function. The only restriction is that those must use only static data MEMBERS of the CLASS. These functions are property of class RATHER than each object.