11.classa {  12. public void process（） { System.out.print（”a，”）； } }  13. class b extends a {  14. public void process（） throws IOException {  15. super.process（）；  16. System.out.print（”b，”）；  17. throw new IOException（）；  18. } }  19. public static void main（String[] args） {  20. try { new b（）.process（）； }  21. catch （IOException e） { System.out.println（”Exception”）； } }  What is the result？（） 

• A、 Exception
• B、 a，b，Exception
• C、 Compilation fails because of an error in line 20.
• D、 Compilation fails because of an error in line 14.
• E、 A NullPointerException is thrown at runtime.