There are three blocks, A, B and C. Block C is below A and block A is below B. Block A contains one medium blue square. Block B has two medium black squares. Medium black square number one is below medium black square number two. And block C has a medium black square and one medium yellow square. The medium black square is below the medium yellow square.
Which object is below a medium black square? the blue thing or the medium yellow square?
the blue thing the medium yellow square  both of them none of them