I would answer reverse global warming and I suppose that would put me in the "idealist" box. :) A lot about interview is just straight up bullshit. Once an interviewer told me a story about a white South African motorcyclist hiking through Africa. He got into an accident outside a small village. The (supposedly black) villages didn't help him at all and instead they just looted his motorcycle and backpack for valuable items. Then after several hours with him laying there another (white) motorcyclist comes around and helps him to the hospital. I didn't realize it at the time, but it was obviously a test. Would I say something racist? Would I respond with "Oh, how awful!"? Would I show any emotion at all?