There are three blocks, A, B and C. Block C is above B and block A is below C. Block A has two medium black squares. Medium black square number one is below medium black square number two. This block also has a medium blue square. The medium blue square is below medium black square number two and medium black square number one. Block B has a medium yellow square. Block C contains a medium black square.
Which object is below a medium black square? medium black square number one or the medium black square which is in block C?
medium black square  number one the medium black square  which is in block C both of them none of them