Which statement is the converse of the following conditional?
 If a polygon has three sides, then it is a triangle. 
A. If a polygon does not have three sides, then it is not a triangle. 
B. If a polygon is not a triangle, then it does not have three sides. 
C. If a polygon is a triangle, then it does not have three sides.
 D. If a polygon is a triangle, then it has three sides.