In the subsequent fogures the circle moves along triangular path. Now we can climinate Answer Figures (2), (3) and (4). The square also moves along triangular path after every two figures. In one step the shaded part of the square moves to the opposite side and in the next step in move along traingular path. Now we can eliminate Answer Figure (1).
The design (Z) descends diagonally stepwise and ascends in one step and after every three figures it is replaced with a new design. The other design ascends in one step and descends stepwise and it is replaced with a new design in each subsequent figure.