Hm... Well this is not gonna be easy.
I would myself say yes it is morally wrong, even if your saving many lives.
Because every life each and every one of them weather it be good or bad has been born into this world not by our hands so who are we to take it away? I don't know how to explain it because I'm not very good at such things, but I will say this.
Even if it is morally wrong to me, I would still have that person sacrificed. Life is a very precious thing and without it we would all die. So why should just one person destroy the many lives of others? Why should that one keep living at the cost of others. Why?
I say no, the guilt of taking a life would be heavy for me, but in order to save more than one person..Then so be it..
I don't know if this makes any sense...But asking if it is Morally Wrong, well that question as you know will get a lot of different opinions. Especially on what the word Moral means to each individual. And because of this more than likely, I think some (or a lot ) of people will state what they think is right instead of what is Morally right..
I hope this makes sense..I can never explain anything right, but I tried my best.