What is the purpose of an inner class?

Nested classes represent a particular type of relationship that is it can access all the members (data members and methods) of the outer class, including private. Nested classes are used to develop more readable and maintainable code because it logically group classes and interfaces in one place only.

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What class must an inner class?

It must extend the enclosing class . Explanation: Option B is correct because a static nested class is not tied to an instance of the enclosing class, and thus can’t access the nonstatic members of the class (just as a static method can’t access nonstatic members of a class).

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