1) If that person could give me sufficient evidence to prove to me that the Earth would in fact destruct (good luck to them), then I think I would say yes. Of course part of me is scared of death, but I would still rather that than living with the guilt of knowing everyone will die with me.
Can you imagine living that kind of life? Not trying anything slightly risky for fear that it might kill you? Doing everything you can to live as long as possible? I'd be afraid of driving, pissing people off in case they have "connections", eating unheathily, etc. A few of the things on my "bucket list" include going skydiving, travelling the world, and climbing a mountain - and I would no longer be able to do those things because they pose a risk to my life. What kind of life is that? I'd rather die.
2) Not once did I (or anyone who picked option 1) criticise you for your choice. (I think, anyway. If we did, sorry.) There are good things about either option:
People who pick option 1 would be sacrificing themselves for the greater good.
People who pick option 2 would be saving their loved ones a lot of pain.
3) It's an experimental quiz. Most experiments will pigeonhole people, whether it is according to height, weight, race, sexual preference, eating habits, etc. etc. This just happens to be pigeonholing according to your academic strengths.
I did state that I (and the person who originally came up with this) know this is a very, VERY broad categorisation. Obviously a whole load of other matters have influenced people's decisions.