toughest sororities during recruitment?

Definitely possible for a sophmore to go through rush and get a bid. The only sororities that are very selective are Phi Mu and DPhiE But KD can be very selective as well.

Phi Mu KD DPhiE

First, yes. It's extremely common for sophomores to go through recruitment.

Historically, PM and DPE make the most cuts on night one.

As fas as how cuts go, every chapter is given a MAXIMUM number of PNMs they have to invite back each round by Panhellenic. It depends on that chapter's performance in the previous years, however, a chapter is NOT given a minimum # they have to invite back. Lets say, hypothetically, there's 1000 PNMs going through recruitment. DDD can only invite back 500, but they decide to invite back 350 instead. They can do this, but their advisers might be against it because it might affect their chances of meeting quota and they'd have to snap bid. A chapter DOES NOT have to invite you back if they do not want you.

So basically, if a chapter invites you back, they see something in you that they like. You should feel honored, and you should have an open mind regardless of which houses cut you. (: You will be in the house you are supposed to be in, that's how the system works. Recruitment will be the best experience enjoy it!