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Inner Classes - Programming

Q1:

class Foo 
{
    class Bar{ }
}
class Test 
{
    public static void main (String [] args) 
    {
        Foo f = new Foo();
        /* Line 10: Missing statement ? */
    }
}
which statement, inserted at line 10, creates an instance of Bar?

A Foo.Bar b = new Foo.Bar();

B Foo.Bar b = f.new Bar();

C Bar b = new f.Bar();

D Bar b = f.new Bar();

ANS:A - Foo.Bar b = new Foo.Bar();

Option B is correct because the syntax is correct-using both names (the enclosing class and the inner class) in the reference declaration, then using a reference to the enclosing class to invoke new on the inner class. Option A, C and D all use incorrect syntax. A is incorrect because it doesn't use a reference to the enclosing class, and also because it includes both names in the new. C is incorrect because it doesn't use the enclosing class name in the reference variable declaration, and because the new syntax is wrong. D is incorrect because it doesn't use the enclosing class name in the reference variable declaration.