Wow. I actually like them all.
I have to go process of elimination - the wave one is cool, but not really very memorable or symbolic of a specific nation. The fourth one bugs me a little with the color palette. That leaves 1 & 2. Black and white is very...well, I like the contrast, but again, doesn't really strike me as emblematic. So, in spite of the red, white and blue motif, the blue is a nice shade and I think that one works the best.