試題詳解

 10. public class SuperCalc{ 

11. protected static int multiply(int a, int b){return a * b；}

 12. }

 and: 

20. public class SubCalc extends SuperCalc{

 21. public static int multiply(int a, int b){ 

22. int c = super.multiply(a, b)；

 23. return c；

 24. } 

25. } 

and: 

30. SubCalc sc = new SubCalc()；

 31. System.out.println(sc.multiply(3, 4))； 

32. System.out.println(SubCalc.multiply(2, 2))；

 What is the result?
(A) 12 4
(B) The code runs with no output.
(C) An exception is thrown at runtime.
(D) Compilation fails because of an error in line 21.
(E) Compilation fails because of an error in line 22.