There are three blocks, A, B and C. Block A is above blocks B and C. Block A contains one big black triangle, a small black square and one big yellow square. Above the big yellow square is the small black square. The big black triangle is below the small black square. It is to the right of the big yellow square. Block B contains a small yellow triangle and one small black circle. Below the small black circle and a small yellow circle is the small yellow triangle. The small black circle is to the left of the small yellow circle. Block C contains one small yellow triangle.
Which object is above a small yellow triangle? the big black triangle or the big yellow square?
the big black triangle  the big yellow square  both of them none of them