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The CORRECT answer is (b) False

Easy explanation - The overloading concept is not related to the types of INHERITANCE being used. Overloading operators can be done without using inheritance. You don’t even have to USE more than ONE class for operator overloading.

Correct choice is (a) Reverse of constructors being called

The EXPLANATION is: The DESTRUCTORS are always called in reverse order of constructors being called always. The type of inheritance doesn’t MATTER. The only important concept is the sequence of classes being inherited.

Correct option is (b) Reusability

The explanation: The code is reusable in most of the classes and the data BECOMES more linked to other classes. Other FEATURES are also exhibited, but the code reusability is used the most. Code readability becomes relatively less. FLEXIBILITY INCREASES but it depends on how the hybrid INHERITANCE is used.

Right choice is (c) Only parent and parent

Easiest explanation - When derived CLASS object is CREATED, all of its successor parent classes CONSTRUCTORS are called. CONSTRUCTOR of all the connected classes is not created. Since the parent MEMBERS have to be initialised, but other derived classes are not needed.

Correct answer is (b) False

To explain I WOULD SAY: The private member’s scope can’t be changed and those can never be accessed in other classes. Only the class CONTAINING private member’s can ACCESS its own members.

The correct ANSWER is (d) None

To EXPLAIN I WOULD say: The use of any specific type is not necessary. Though the final structure should not be the same, it should REPRESENT more than one type of inheritance if class DIAGRAM is drawn.

Right answer is (d) Constructor calls are usual

Easiest explanation - The CONSTRUCTORS will be called in usual way. First the PARENT class Constructor and then the derived class Constructors. This is DONE to INITIALISE all the members PROPERLY.

Correct choice is (a) Hierarchical

To explain I would SAY: Hierarchical inheritance is deriving more than ONE classes from a base CLASS, it it is done continuously and subsequently, it results forming a tree like STRUCTURE of classes being linked.

Right answer is (b) Multilevel

The best explanation: The statement REPRESENTS multilevel inheritance. It is not hybrid since looking at complete idea, one can’t DIFFERENTIATE whether two type of inheritance are USED. HENCE it is multilevel inheritance.

The CORRECT option is (b) At LEAST 2

Easy explanation - There must be COMBINATION of at least 2 types of inheritance. The inheritance should be of different type.

Right ANSWER is (a) Combination of two or more inheritance types

Explanation: When more than one type of inheritance are used together, it RESULTS in new type of inheritance which is in general known as HYBRID inheritance. This MAY of may not have BETTER capabilities.

Correct ANSWER is (b) False

The best I can explain: The derived classes have full ACCESS to all the NON private member’s of base class. Every derived class have equal access, none of the class can have SPECIAL access to specific members of base class in general cases.

The correct choice is (C) Hierarchical

For explanation: When hierarchical inheritance is used, the COMMON syllabus can be adopted into different college CLASSES where the same syllabus is applicable. For changing the syllabus only the details of base class will have to changed.

Correct answer is (a) Hybrid inheritance

To explain: When we USE hybrid inheritance, it can contain any type of inheritance or combination or more than TWO TYPES. HENCE it may contain Hierarchical inheritance too, hence it can be subset of hybrid inheritance.

Correct option is (d) Hierarchical inheritance allows inheritance of common features to more than one class

Best explanation: Hierarchical inheritance is USED to make all the inherited classes have some common features obtained from a single base class. This allows all the classes to MAINTAIN a GROUP or to be classified under one class.

The CORRECT answer is (b) False

To explain I would say: The classes are independent and can access the base class and INHERIT it in whichever WAY it is required. The classes can USE the base base class members privately or publically maintaining the security of data and METHODS.

Right choice is (a) As many as REQUIRED

The best explanation: The number of classes that can be DERIVED from a base class doesn’t have any restriction and HENCE will be able to derive as many classes as required. This FEATURE GIVES more flexibility and code reusability.

The correct option is (a) Private

Explanation: All the DERIVED CLASSES must use private inheritance. This will make the members of base class private in derived classes. HENCE NONE of the members of base class will be AVAILABLE for further inheritance.

Right CHOICE is (b) At least 3

The best I can explain: At least 3 classes MUST be there. TWO derived classes and one base CLASS. This lets us IMPLEMENT two classes that have common characteristics from base class.

Correct answer is (a) Independently using any inheritance

Best explanation: The CLASSES can INHERIT the base class using any type of inheritance. There is no MANDATORY condition to use same private,public or PROTECTED inheritance only.

The correct option is (c) No, it’s doesn’t get DIVIDED

The explanation: The CLASS members doesn’t get divided AMONG the child classes. All the members get derived to each of the subclasses as whole. The only restriction is from the ACCESS SPECIFIERS used.

Right option is (a) More than one classes being DERIVED from one class

Easiest explanation - When two or more classes get derived from a single base class, it is known as hierarchical INHERITANCE. This gives US freedom to use same code with DIFFERENT scopes and flexibility into different classes.

Right choice is (d) No, since constructors won’t be there

The best explanation: The derived CLASS must not be ABSTRACT. This is because the abstract classes doesn’t have CONSTRUCTOR and hence we won’t be having the capability to have instances. This will restrict the use of MULTIPLE INHERITANCE.

The correct answer is (a) Private MEMBERS of base

The best I can explain: The private member’s are AVAILABLE for only the class containing those members. DERIVED classes will have ACCESS to protected and public members only.

The correct choice is (a) No, only SINGLE LEVEL inheritance is used

The best I can explain: When a class having NESTED classes is being derived into another class. It INDIRECTLY means a simple class is being inherited to another class. This is single level inheritance.

Correct ANSWER is (b) Yes, only if no abstract class is involved

Explanation: The constructors must be DEFINED in every class. If class is abstract, it won’t have any CONSTRUCTOR but other CLASSES must have constructor. Either IMPLICIT or explicit.

Right option is (a) There won’t be any use of multiple inheritance

To EXPLAIN: The derived class will not be able to access any members of the base CLASSES. Since PRIVATE MEMBER’s are not inheritable. It leads to no use of multiple inheritance.

Right option is (a) Derived class object

The best explanation: The derived class object can access all of its own members. It can ALSO access the available members of the PARENT classes, because the members are derived into the derived class.

Correct choice is (C) Using virtual keyword with same name function

To explain I would say: To overcome the ambiguity and CONFLICT we can use keyword virtual. This will HELP us to differentiate the functions with same name that came to last derived class in DIAMOND PROBLEM.

Right ANSWER is (d) As many as required

For explanation: The classes can derive from as many classes as required since the multiple inheritance feature is made to combine or GROUP together the functions that are from different classes. This MAKE the DERIVED class stronger in terms of its flexibility.

Right answer is (a) Methods with same name creates ambiguity and conflict

For EXPLANATION: All the DERIVED classes can distinguish the base CLASS members, but if a method is being inherited to the base classes from another class which again gets inherited into same class (diamond SHAPE), that may CREATE conflict in using the function from two available.

The correct OPTION is (B) CLASS B

Best explanation: The constructors of parent class will be called first. In that, the constructor of the classes will be called in the same sequence as that mentioned in class definition inheritance. Since class B is mentioned first for inheritance, its constructor will be called first.

Correct option is (d) JAVA

For explanation: Java doesn’t allow use of multiple inheritance with classes. But this can be done by USING the interfaces. This is more SECURE and unambiguous way to IMPLEMENT multiple inheritance.

The correct ANSWER is (C) At LEAST 3

The best I can explain: For the IMPLEMENTATION of multiple inheritance, there must be at least 3 CLASSES in a program. At least 2 base classes and one class to inherit those two classes. If lesser, it becomes single level inheritance.

Right option is (a) Diamond

The explanation is: The diamond problem arises when multiple INHERITANCE is used. This problem arises because the same name MEMBER functions get derived into a SINGLE CLASS. Which in turn creates AMBIGUITY in calling those methods.

The correct choice is (b) When a class is derived from TWO or more classes

Easiest EXPLANATION - The multiple inheritance is used when a class is being derived using two base classes or more. This way a single class can have features of more than one classes inherited into a single unit. This lets us combine two class MEMBERS into a single class.

The correct choice is (c) Code reusability

The best explanation: The CLASSES using MULTILEVEL inheritance will use the code in all the subsequent subclasses if available. Hence the most significant feature among the options GIVEN is code reusability. This feature is generally INTENDED to use the data values and reuse the redundant functions.

The correct answer is (b) Object of lower LEVEL classes must call parent class constructors explicitly

The best I can EXPLAIN: Each class constructor must be called before creating the object of any subclass. HENCE it will be mandatory to call the constructors of parent classes explicitly with parameters. This will make all the previous class MEMBER be initialized and then the class in use will be able to CREATE the object.

The correct ANSWER is (c) At least one LESS than number of levels

Easiest explanation - At least one CLASS must implement all the UNDEFINED functions. Hence there must be at least one class which is not abstract. That is at least one less than number of levels.

The correct OPTION is (b) False

The best I can explain: There is no mandatory RULE to make the MEMBERS private for multilevel INHERITANCE. Moreover, if all the classes have only the private members then there won’t be any member to GET inherited. Hence the working will be of no use.

The correct CHOICE is (a) Only one class

The best I can EXPLAIN: The CLASSES INHERIT only from one class. This CONTINUES as each class inherits only one class. There should not be any class that inherits from two or more classes or which have more than one subclass.