The fourth question only looks at the left side of each picture. The shadow circle in the first picture is the first from top to bottom, the shadow circle in the second picture is the second from top to bottom, and the shadow circle in the third picture is the third from top to bottom, so the shadow circle in the fourth picture should be the fourth from top to bottom.

Similarly, just looking at the right, the hatched circle in the first picture is the first from bottom to top, the hatched circle in the second picture is the second from bottom to top, and the hatched circle in the third picture is the third from bottom to top, so the hatched circle in the fourth picture should be the fourth from bottom to top.