There are three blocks. Lets call them A, B and C. Block A has a medium black square. Below block A there is block B with a medium blue square in it. This block also has one medium black square. It also has a medium yellow square. It is below the medium blue square. Below the medium object which is below the medium blue square there is the medium black square. It is below the medium blue square. Below block A there is block C. It contains a medium blue square.
Which object is below a medium black square? the medium yellow square or the black thing that is touching the bottom edge of a block?
the medium yellow square  the black thing that is touching the bottom edge of a block  both of them none of them