There isn't a number in the first picture. It might be an example of how a dog might see it. They have black white and brown supposedly. These things usually have pastels of red green/yellow or blue. You usually think of light coming from above, So B should be indented and C should be sticking out. But they both look like they're sticking out to me too. I think it's just because the green box is large enough that the edge falls outside my peripheral vision. Anyway when I read I only use about the inside 2 degrees of my vision. The edge is 4 or 5 degrees from the dot where I am sitting in front of my monitor. I keep looking over to the edge on B and C to try and find another reference, a shadow or something to sort them out. Because there isn't any the dot with the more detail gets pulled to the center of my attention (closer) in each case. Hope this helps:0)