Which code, inserted at line 14, allows the Sprite class to compile?

Given:
10. class Nav{
11. public enum Direction { NORTH, SOUTH, EAST, WEST }
12. }
13. public class Sprite{
14. // insert code here
15. }
Which code, inserted at line 14, allows the Sprite class to compile?

A.
Direction d = Direction.NORTH;

B.
Nav.Direction d = Nav.Direction.NORTH;

C.
Direction d = NORTH;

D.
Nav.Direction d = NORTH;