Judging by the variety of opinions above, I would say that the game is conclusive: people here can't tell which camera is which.
My opinion is that:
-I find B the worst, because of a green-yellow color balance.
-A is a bit darker and a bit more saturated than C. I think I prefer C, the skin structure seems a bit more natural. A seems to exaggerate the red colour of the cheeks as well (as brought by the make-up).
Obviously, the model is a beautiful young lady, but if you could redo the test with someone of caucasian descent and a little bit less make-up, maybe the difference would be more obvious. In any case, I always enjoy looking at beautiful young women, so feel free to test us again!
(Actually, you can even try with male models. We do have some female photographers here...)