Group the given figures into three classes using each figure only once.
A.
1,3,9 ; 2,5,6 ; 4,7,8
B.
1,3,9 ; 2,7,8 ; 4,5,6
C.
1,2,4 ; 3,5,7 ; 6,8,9
D.
1,3,6 ; 2,4,8 ; 5,7,9
Correct answer is A
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.