Rather odd and incredibly unlikely scenario is it not?
First off this is coming from a guy who has had lot's of human's let him down or outright bully him while living around animals and pet's who have been generally incredibly kind-hearted and understanding
It would depend on ALOT of different factors for me, the idea of pitting an animal vs a human life is a difficult one for me, it generally depends on my relationship with either of them, assuming I have no idea who either of them are and saving either one is equally risky in every way... ehhh I would probably save homeless guy, but yeah... either way I'm going to be feeling guilty for the rest of my life... If it's not that simple (which is very likely) it would depend on my relationship with either party, if one is less risky to save than the other etc.
If I know the kittens and don't know the homeless guy, I gotta be honest i'm saving kittens
If I know the homeless guy is an assholish drunkard with no family... well call me crazy or whatever but screw the human asshole, i'm saving kittens, that said though if I know homeless guy and he's a generally kind and decent human being and I don't know kittens I'd save homeless guy
Overall for you TL;DR it would depend on alot of different thing's but overall if it's a random stranger vs a random animal... I would lean towards animals but only slightly more, the second I know the homeless man is an asshole... yup he gunna die