An automatic box was the property of the company. The box contained a slit of sufficient size to admit a coin and a projecting button. The box was so constructed that upon a coin being dropped into the slit and the button being pushed in, a chocolate would be ejected from the box. 'A' dropped into the slit a brass disc about the size and shape of the coin, and thereby obtained a chocolate. 'A' is

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 */ } }F. public abstract class Circle implements Shape { private int radius; public void draw() { /* code here */ } }