The correct option is A 1, 5, 7; 3, 4, 8; 2, 6, 9
We can see that the shapes 1, 5, and 7 have one shape inside another. So, they form one group.
The shapes 3, 4, and 8 have one shape beside another. So, they form one group.
The shapes 2, 6, and 9 have two lines inside a shape. So, they form one group.
Hence, the correct answer is 1, 5, 7; 3, 4, 8; 2, 6, 9.