Three positions of a cube with shapes on its faces are shown. In the fourth position the diamond is on the left and the circle on the right. Which shape is on top?

The triangle and the square appear in (i) and (ii), so the circle and the star are opposite. The square touches the circle, triangle, star and diamond, so the square is opposite the plus sign, and the triangle is opposite the diamond. With the diamond on the left and the circle on the right, the top is a neighbour of both: the square or the plus sign. Picture (iii) shows the diamond, circle and square at one corner in the same order, so the top is the square.