What is the legal clone() methods when subclassing Object? : Questions « Utility Classes « SCJP

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3. Questions

A.  public Object clone() { return super.clone(); }
B.  public Object clone() throws CloneNotSupportedException { return super.clone(); }
C.  public Q13 clone() { return (Q13)super.clone(); }
D.  public Q13 clone()  throws CloneNotSupportedException { return (Q13)super.clone(); }