I've found the following puzzle:
I think the answer is
5.
In the first row, the 1 can be explained by the red ball.The second row is a bit different. Instead of looking at the second row to explain the number 2, look at the first row. You'll see 2 red rings. The third row is similar to what we came up with. Ignore the objects in the third row and count the red rings in row 1 and 2. We'll see 4 altogether. The fourth row is like the first row; count all the red balls you've seen from that point. We can count 5.
But I'm just not satisfied with what i have here. Maybe you guys can come up with something?