1. public interface A { 2. public void doSomething（String thing）； 3. } 1. public class AImpl implements A { 2. public void doSomething（String msg） { } 3. } 1. public class B { 2. public A doit（） { 3. // more code here 4. } 5. 6. public String execute（） { 7. // more code here 8. } 9. } 1. public class C extends B { 2. public AImpl doit（） { 3. // more code here 4. } 5. 6. public Object execute（） { 7. // more code here 8. } 9. } Which statement is true about the classes and interfaces in the exhibit？（） A. Compilation will succeed for all classes and interfaces.B. Compilation of class C will fail because of an error in line 2.C. Compilation of class C will fail because of an error in line 6.D. Compilation of class AImpl will fail because of an error in line 2.

单项选择题

1. public interface A {
2. public void doSomething（String thing）；
3. }
1. public class AImpl implements A {
2. public void doSomething（String msg） { }
3. }
1. public class B {
2. public A doit（） {
3. // more code here
4. }
5.
6. public String execute（） {
7. // more code here
8. }
9. }
1. public class C extends B {
2. public AImpl doit（） {
3. // more code here
4. }
5.
6. public Object execute（） {
7. // more code here
8. }
9. }
Which statement is true about the classes and interfaces in the exhibit？（）

A. Compilation will succeed for all classes and interfaces.
B. Compilation of class C will fail because of an error in line 2.
C. Compilation of class C will fail because of an error in line 6.
D. Compilation of class AImpl will fail because of an error in line 2.

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