For me, it's B. That's not to say I don't find Alyssa very sexy in picture A, but for me personally I've always found subtle eroticism to be stronger in photos where the model isn't smiling/laughing unless it's that slight, coy "come and get it" smile, or the more explicit "tongue running over lips" smile with intense eyes in the traditional "making love to the camera" type of expression. I usually appreciate photos more where I can feel some intensity coming out of the model, and often a smile or laugh takes that intensity away and transforms it from an erotic image into "model is doing whatever she is doing, but she just happens to be naked." It's a very personal, subjective answer, but my answer it is. I knows what I likes. B.