During recruitment my freshmen year (before I transferred), I was asked this question on Pref Night by the only chapter I was preffing... I answered that I was only attending that party that night. The girl who was preffing me told me that maybe that was best. I agreed with her, but the rest of the party was strained and awkward. In hindsight, I'm not sure why... but it was. I didn't receive a bid from that chapter - but it really was for the best. I transferred back home the next semester and found my real home!
Moral of the story: Don't ask that question. It can make things very awkward.