We have three blocks. Lets call them A, B and C. There is one medium black square in block A. A medium blue square is below the medium black square. Then, we have block B. It contains a medium yellow square. Finally, below block B we have block C. It is below block A. It contains two medium black squares. It also contains a medium blue square. Below medium black square number two there is the medium blue square. It is below medium black square number one which is below medium black square number two.
Which object is below a medium square? the medium black square that is in block A or medium black square number one?
the medium black square  that is in block A medium black square  number one both of them none of them