There are three blocks. We call them A, B and C. Block A contains one small blue triangle. Below block A is block B. It contains a big black circle, a big blue triangle and a medium yellow square. The big black circle is touching the bottom edge of this block. Below the medium yellow square there is the big blue triangle. Below and to the left of the medium yellow square is the big black circle. Finally, there is block C which is to the left of block A. It contains one small black circle.
What is below the small blue triangle? a small black circle or a medium yellow square?
small black circle  medium yellow square  both of them none of them