Answer:
A. The 2 groups could be quadrilateral and triangles.
quadrilateral-1,2,,6,7
Triangles-3,4,5,8,9
B.You could also sort them into shapes with 4 sides and shapes with 3 sides.
4 sides-1,2,,6,7
3 sides--3,4,5,8,9
C. They are all polygons becuase they all have 3 or more striaght sides and they all are closed shapes.
Explanation: