I would stick with B team but that is from my experience.
I 100% agree with RJM and his example is perfect.My son played on travel teams every summer that hit a lot of hi profile summer tournaments (not a top national showcase team - a club team). Recruiters and scouts go to these showcases with a list of players already. When those players hit/pitch - they watch. When those players are done - they leave or generally not really watching the game. My son is a good player but he is not good enough to turn heads at these kind of showcases and unless you are on their list (due to skills already measured) or do something outstanding like hit bombs - they are not watching you.
Its been said on this forum many times - "fish in the right pond". My son wants to be an engineer and play baseball. Well, that means D1 is pretty much out (not that my son is a d1 talent - he is not - but even if he was - very, very difficult at d1 school). That leaves some D2 but mostly D3 schools that offered his particular major. We would have been much better off targeting the summer camps of these perspective schools than playing on a summer travel team. I feel we wasted a lot of money trying to get "exposure" at these national showcase/tournaments.
Luckily for us - and with a lot of advice and experience from this website we have found what we think will be a great fit for him. An engineering school that has an excellent baseball program. Everyone on team is an engineer so all the kids are in same boat in regards to academics vs sports.
Sorry for the long post but the most important decision is figuring out what skill level your son is at - what his dreams/aspirations are on playing in college - and developing a plan around those goals. This may or may not include travel/showcase teams.