There are two blocks, A and B. Block A contains a small blue square. One small blue triangle is also in this block. The small blue square is to the left of and above the small blue triangle. Block B is to the left of block A. It contains a big yellow triangle and one medium blue square. The big yellow triangle is touching the right edge of this block. A big black square is below the medium blue square. To the right of the medium blue square and the big black square is the big yellow triangle.
Which object is to the left of a small blue square? the big black square or the medium blue square?
the big black square  the medium blue square  both of them none of them