There are three blocks. We call them A, B and C. Block B is above A. Block C is below B. Block A contains a medium blue square, a big yellow triangle and a small black triangle. Below the small black triangle is the medium blue square. The big yellow triangle is touching the bottom edge of this block. This shape is below the small black triangle. Above the big yellow triangle is the medium blue square. Block B contains a medium black square. And block C contains one medium blue triangle.
What is below the medium black square? a big triangle which is touching the bottom edge of a block or a medium blue square?
big triangle  which is touching the bottom edge of a block  medium blue square  both of them none of them