Explanation: In the given chunk of code, Class B1 is a base class. Class B2 is derived class of class B1. Class B3 is derived class of B2. As you can see class B1 has two members or instance variables i and j. Instance variable cannot be directly accessible by both B2 and B3. If you see this statement of the given code private int j; the keyword private is used with the variable j. This keyword is called access specifier. Access specifiers specifies how the members of a class can be accessed. These members are attributes and methods of that class. Any member of a class that are declared private cannot be inherited by derived classes of that class. Additionally these private members cannot be accessed from within any method inside derived class. So j is directly accessible only in B1. You can access a private instance variable from within the same class or can access it through the methods of class.
