Group the given figures into three classes using each figure only once.
A.
3,4,9 ; 5,7,8 ; 1,2,6
B.
1,5,6 ; 2,4,8 ; 3,7,9
C.
4,6,8 ; 3,5,7 ; 1,2,9
D.
1,2,7 ; 3,5,9 ; 4,6,8
Correct answer is D
1, 2, 7 are simple geometrical figures.
3, 5, 9 have one element placed inside a different element.
4, 6, 8 have two different elements attached to each other.