There are three blocks, A, B and C. A medium black square, one medium yellow square and one medium blue square are in block A. The medium black square is below the medium blue square. The medium yellow square is below the medium blue square. Below the medium yellow square is the medium black square. Below block A is block B. It contains a medium black square. Finally, there is block C to the left of block A. It contains one medium black square.
What is below the yellow object? a medium black square or a blue thing?
medium black square  blue thing both of them none of them