There are three blocks, A, B and C. Block A has one medium black triangle, one medium black square and one big blue triangle. The medium black triangle is touching the bottom edge of this block. To the right of the big blue triangle is the medium black square. Below and to the left of the medium black square is the medium black triangle. It is below the big blue triangle. Block B is below block A. It has a small black square. To the left of block A there is block C. It has one small blue square and one big yellow square. The small blue square is above and to the right of the big yellow square.
Which object is to the left of a medium black square? the small black square or the big yellow square?
the small black square  the big yellow square  both of them none of them