The difference between A and B is the low end. Mix (A) had more low end energy which obviously made it more bassy. None of the mixes rolled off the subsonics(40Hz on down), which is something you may consider doing. Between Mix A and B, I preferred B because the low end seemed more balanced overall.
The difference between Mix B and C is the hi end; Mix (C) has more energy in the 5Khz - 15Khz range the best I can tell. I prefer Mix C to B.