Thank you for the advice!
The issue is, I prefer the program of Program A and it is top 50 (but barely). I would be happy there. However, I significantly prefer the professor (and research they do) at Program B (which is barely top 100). I know Program A's a better program, but working with the professor at Program B is kind of my dream. But my biggest dream is to be tenure track.
MathCat, do you know where I can learn more about that (about possibility of getting tenure-track in a top 100 program?)