Three things happen to every shape when A becomes B. Find all three and apply them to C.

Each shape moves one quarter anticlockwise (top-left to bottom-left, bottom-right to top-right), swaps orange for blue or blue for orange, and gains one side (triangle to square, square to pentagon). In C the orange pentagon moves to the top-left and becomes a blue hexagon, the blue triangle moves to the bottom-right and becomes an orange square, and the orange square moves to the top-right and becomes a blue pentagon: (d). (a) forgets the colours, (b) moves clockwise and (c) forgets the extra side.