i would say 6 seasons of track cause it shows your commitment. they like activities that you stick too instead of 20 random ones.. but the wrestling still looks good since youve had several seasons. if your a track star stick with track, if your a star wrestler then go to that.
Assuming you've completed one or the other, it's somewhat a moot point. However, to answer your question, both are fine. USNA recognizes that wrestling is only offered for one season a year vs. two for track. In both cases, you've been a varsity letter winner for three straight seasons -- that's good.
If you wrestle, make sure you do plenty of running. If you run, make sure you have sufficient upper body strength to do pull-ups and push-ups. You need both (running skills and upper body strength) for plebe summer and for PT tests at USNA.