Given：

What is the result？（）

A.public class Circle implements Shape {private int radius；}
B.public abstract class Circle extends Shape {private int radius；}
C.public class Circle extends Shape {private int radius；public void draw（）；}
D.public abstract class Circle implements Shape { private int radius；public void draw（）；}
E.public class Circle extends Shape {private int radius；public void draw（） {/* code here*/}}

A.Compilation fails.
B.An exception is thrown at runtime.
C.The code executes normally and prints "foo".
D.The code executes normally， but nothing is printed.

A.The output could be 5-1 6-1 6-2 5-2
B.The output could be 6-1 6-2 5-1 5-2
C.The output could be 6-1 5-2 6-2 5-1
D.The output could be 6-1 6-2 5-1 7-1