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