Given：  
11. static class A {  
12. void process（） throws Exception { throw new Exception（）； }  
13. }  
14. static class B extends A {  
15. void process（） { System.out.println（"B "）； }  
16. }  
17. public static void main（String[] args） {  
18. A a = new B（）；  
19. a.process（）；  
20. }  
What is the result？ （）

A. Compilation fails because of an error in line 19.
B. An exception is thrown at runtime.
C. B
D. Compilation fails because of an error in line 18.
E. Compilation fails because of an error in line 15. 
F. The code runs with no output.