I voted for everything, give me a few more options and I will vote for that too.
Im an advocate for defending your BB, but with small blinds, if he had a weak hand why didnt he just call.. he is UTG so any raise even small has to be treated as a strong hand... (unless you know him/read otherwise)
I would call, and if the flop came low cards, I would bet a pot sized bet, assuming it is just you two heads up.
he could have so many cards it is hard to say, if he re-raises you maybe he has a mid pocket pair, or high pocket pair, or... a draw if there is one
hard to say, but I go with call/raise