Believe it or not, square A and B are the same color. Don't believe it, put it in Photoshop and see. Use the select color tool, it should give you the same color (787878)..
http://i140.photobucket.com/albums/r...lusion4med.jpg
Here's the proof:
http://i140.photobucket.com/albums/r...double_med.jpg
Now if you'll excuse me~ my head hurts