The right type of person can both play college sports and undertake a challenging major. I tried to do it with Engineering but with my personality it was difficult. By nature I am the type of person who has a hard
time seeking balance. I was trying to study all night and then get up and go to practice in the winter at 6 am. I also tried to always get extra reps in the cage and in the field, like I had when I was in HS (and younger).
It ended up being too much, I got sick (mono) and ball no longer was fun so I made the decision to
quit even though I was starting. However I realize now that I didn't need to study that much nor did I need to always be the first one to practice and the last one to leave. If I had made that realization earlier I might have been able to do both. While everything
ultimately worked out fine, there are times I wish somebody had told me to take a breath...
IMO, by 16U if she is not 100% sure if she wants to play in college, then think you have your answer. Stay with her friends on the "B" team and enjoy the time with them. The other factor is having time for school work and study. If she is on the travel ball team, it eats away at her study time, when grades are the most important (sophomore - senior years).
To be your best at something, you have to hang around people who also are "the best". There is no other way. If she wants to play in college, she has to go with a team that has the better players. The whole point of being on a team with other good players is that it will force her to elevate her game.
If she wants to play "for fun", she can stay on the team with her friends. There is nothing wrong with that...but, her development as a player will be diminished.