We have three blocks. We call them A, B and C. Block B is below A and block C is to the left of B. Block A contains a medium black square. Block B contains three medium blue squares. Medium blue square number one is touching the bottom edge of this block. Medium blue square number two is below a medium black square which is below medium blue square number three.. Below medium blue square number three , medium blue square number two and the medium black square there is medium blue square number one. And block C contains a medium yellow square.
What is above the thing which is touching the bottom edge of a block? a medium black square or a medium yellow square?
medium black square  medium yellow square  both of them none of them