Figural Classification — quick quiz

Six figures are given below. Five of them form a group based on a certain rule. Which figure does NOT belong to this group? Figure A: A square with its diagonals drawn, creating 4 triangular sections, with opposite triangles shaded Figure B: A circle divided into 4 equal sectors, with opposite sectors shaded Figure C: A rectangle with its diagonals drawn, creating 4 triangular sections, with opposite triangles shaded Figure D: A rhombus with its diagonals drawn, creating 4 triangular sections, with opposite triangles shaded Figure E: A pentagon divided into 5 equal parts with alternate parts shaded Figure F: A hexagon divided into 6 equal parts, with opposite parts shaded