We have three blocks, A, B and C. Block A contains a medium yellow square. Below the medium yellow square is a big yellow triangle. Below block A we have block B with a big yellow circle in it. Above block A there is block C with one small blue square in it. It also contains one medium yellow circle. Above the medium yellow circle there is the small blue square.
What is above the big yellow circle? a big triangle or a medium yellow square?
big triangle  medium yellow square  both of them none of them