问题：

[单选]

10. public class SuperCaic { 
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.
F .  Compilation fails because of an error in line 31.