Group the given figures into three classes using each figure only once.

   

1,5,7 contain a rectangle with its two diagonals as the outer element and another element (similar or different) placed inside it.

2,6,9 contain a triangle with its three medians as the outer element and another element (similar or different) placed inside it.

3,4,8 contain a circle with its two mutually perpendicular diameters as the outer element and another element (similar or different) placed inside it.

1,6,8 are figures composed of straight as well as curved lines

3,7,9 are closed figures shaded by oblique line segments

2,4,5 are figures composed of straight lines only.

5,8,9 are objects having both base as well as upper lid. 

2,3,6 are objects having base but not upper lid. 

1,4,7 are objects which have neither a base nor an upper lid attached to them.

1,3,9 have one element placed inside a different element.

2,5,6 contain two mutually perpendicular lines dividing the figure into four parts.

4,7,8 have two similar elements (unequal in size) attached to each other.

1, 6, 9, are all triangles.

3, 4, 7 are all four-sided figures.

2, 5, 8 are all five-sided figures.

1, 2, 3 are figures composed of two straight lines.

4, 5, 6 are figures composed of three straight lines.

7, 8, 9 are figures composed of four straight lines.

1, 7, 8 are all undivided geometrical figures.

3, 5, 6 are geometrical figures divided into two parts.

2, 4, 9 are geometrical figures divided into four parts.

1, 3, 6 contain one complete circle each.

2, 5, 7 contain a semi-circle each. 

4, 8, 9 contain a triangle each.