單項選擇題

1. class A { 
3. public String to String() { 
4. return “4”; 
5. } 
6. } 
7. class B extends A { 
8. public String toString() {
9. return super.toString() + “3”; 
10. } 
11. } 
12. public class Test { 
13. public static void main (String[] args) { 
14. System.out.printIn(new B());
15. } 
16. }  
What is the result()?  
 

A. Compilation succeeds and 4 is printed.
B. Compilation …………… is printed.
C. An error on line 9 cause compilation to fail.
D. An error on line 14 cause compilation to fail.
E. Compilation succeeds but an exception is thrown at line 9.

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