I am partial to Cover B because it has a simpler design. When I view a book cover I don't want to take extra time to figure out what's going on. Cover A has too many levels to digest. Cover B is quick and to the point. Cover A isn't crisp and clean--in my opinion it looks messy.
Without a doubt, Option A. The photo stands out, the colors more vivid, and I also like the back cover much better, the font is easier to read. Good luck with you first novel.