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