There are three blocks, A, B and C. Block B is below block C and to the right of block A. Block A has one medium blue triangle. Block B contains one medium yellow circle. The medium yellow circle is below and to the left of a small black triangle. Block C has a big blue triangle and one big blue square. The big blue triangle is near to and above the big blue square.
What is above the black triangle? a medium yellow circle or a big square?
medium yellow circle  big square  both of them none of them