Pick the major (not regional) you'd most want to work at and most likely to be hiring in 2018.
It's an incredibly powerful thing to click the box that says "I worked here previously..." My buddy co-oped at Delta and was one of the first hired in 07. He got me in a year later and the funny thing is I graduated college and went to the airlines while he was still on his instrument. IT PAYS TO INTERN/CO-OP.