Non-Verbal -Grouping of Identical Figure

DIRECTIONS : Group the following figures into three classes on the basis of identical properties.
Examples :

1.
  A.  1,7,9 ; 2,3,6 ; 4,5,8 B.  1,2,9 ; 3,4,6 ; 5,7,8
  C.  1,6,8 ; 2,4,7 ; 3,5,9 D.  1,7,8 ; 2,9,3 ; 6,4,5
  Solutions : A.
1,7,9 contain two similar elements one inside the other but not touching each other.
2,3,6 contain two similar elements one inside the other and both touching each other.
4,5,8 are divided into equal parts by straight lines the other and both touching each other.