There are two blocks. We call them A and B. There are a medium black square and one medium yellow square in block A. Below the medium black square which is below the medium yellow square there is a medium blue square. It is below the medium yellow square. Block B is below block A. It has a medium black square. Below the medium black square there is a medium blue square.
Which object is below a medium square? the medium black square which is in block B or the medium black square which is in block A?
the medium black square  which is in block B the medium black square  which is in block A both of them none of them