There are three blocks. We call them A, B and C. There is one medium black square in block A. Below a medium yellow square there is the medium black square. Then, there is block B. It contains a medium yellow square. Block C is below blocks B and A. It contains a medium black square and one medium yellow square. The medium black square is below the medium yellow square.
Which object is above a medium black square? the medium yellow square which is in block C or the medium yellow square that is in block A?
the medium yellow square  which is in block C the medium yellow square  that is in block A both of them none of them