The orange cell and the blue star both move round the outer cells of the grid. The orange cell's move is not the same every time. Which grid comes next?

The orange cell moves clockwise 1, 2, 1, 2 cells in turn, so the next move is 1 cell: from the bottom-left corner up to the middle-left cell. The star moves 1 cell anticlockwise every time, from the top-right corner to the top-middle cell: (c). (a) repeats a 2-cell move, (b) sends the star clockwise and (d) leaves it still.