which is the smartest fraternity?

I am a rising sophomore planning on rushing when I get back to campus, but I have some questions about which frat would be best for me. I was wondering which frat, in general, has the smartest guys. This could be based on gpa, but also from personal experiences of which group of guys seem to be the most intelligent. Also, how is fall rush for sophomores? Is it pretty competitive, or is it fairly certain that most guys will get bids? Thanks for the help!