There are three blocks, A, B and C. Block A has one medium yellow square. Then, there is block B which has two medium black squares. Medium black square number one is below medium black square number two. Block C is below both blocks B and A. It contains one medium blue square and one medium black square. The medium blue square is touching the bottom edge of this block. It is below the medium black square.
What is above the blue shape? a medium black square or a medium yellow square?
medium black square  medium yellow square  both of them none of them