There are two blocks, A and B. There is one medium yellow square in block A. Block B is above block A. It contains two medium black squares. Below a medium yellow square and medium black square number two is medium black square number one. Below medium black square number two , the medium yellow square and medium black square number one is a medium blue square.
Which object is above a medium yellow square? medium black square number two or medium black square number one?
medium black square  number two medium black square  number one both of them none of them