You are missing option d), raise the standard of living so that no one lives in poverty, and no one feels that stealing is the best way to get what they want.
I mean it's not like there are dozens of confounding factors that make it a complicated problem like mental health issues, disabilities, immigration, substance abuse, or a dozen other things.
No it's probably all just the evil capitalist class, if we just got rid of them then everyone would be equal and joy and peace would exist forever just like in the Soviet Union known as a bastion of joy and freedom and peace, and they had practically no crime to boot. Was it because of a totalitarian police state that banished people to die in the frozens wastes of Siberia for life? No it was because the capitalists were gone that's clearly the solution.
Because ubi would 100% eradicate poverty as we currently define it: making under a certain income level. Would it improve living situations or get rid of stealing as a “best way to get what you want”? Idk - but it seems clear it’d work better than what we’re currently doing (systematically impoverishing millions because otherwise nobody would get to own a superyacht)
Speaking as a foreigner, it seems to me that this whole "USA #1" mentality is keeping a lot of people from reflecting on the reality of their situation and from being willing to try and make things better, as is evidenced by the person I was responding to - to paraphrase a bit their take seems to be "we're the best so we can't possibly fix the problem". That argument doesn't really make sense if you're actually not.
I completely agree that there will still be thieves in a post-scarcity utopia, but those will basically just be bored housewives looking for a thrill. We should definitely work on reducing the number of people who resort to stealing in order to survive, though.