We have three blocks. Lets call them A, B and C. Block A contains a medium blue square and a medium black square. The medium blue square is touching the bottom edge of this block. This object is below the medium black square. Block B is below block A. It contains a medium yellow square. There is also a medium black square in this block. The medium black square is below the medium yellow square. Below block B there is block C. It has a medium yellow square.
What is below the blue thing? a medium black square that is in block A or a medium black square that is in block B?
medium black square  that is in block A medium black square  that is in block B both of them none of them