what are the top pre-med universities?

Answer 1

There's really no such thing.

First of all, med schools don't care what major you are. They just want to make sure you take all the classes they require. They prefer that you come from a challenging educational program. That typically means the higher ranked school. However, you have to weigh that against the likelihood of higher competition. A 2.0 from Harvard isn't going to look impressive to a med school, even if it is from Harvard.