Which is true?
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"X extends Y" is correct if and only if X is a class and Y is an interface
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"X extends Y" is correct if and only if X is an interface and Y is a class
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"X extends Y" is correct if X and Y are either both classes or both interfaces
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"X extends Y" is correct for all combinations of X and Y being classes and/or interfaces
Reveal answer
Fill a bubble to check yourself
C
Correct answer
Explanation
In Java, the 'extends' keyword can only be used when both X and Y are classes (class inheritance), or when both X and Y are interfaces (interface inheritance). A class extends another class, and an interface extends another interface. A class implements an interface, not extends it.