I think it is A, though it is not much of an inference.
We don't know anything about the population breakdown. It is not B.
We don't know if there was any payment made. The tone of the last sentence of the quotation suggests there was no payment made. C doesn't work.
D is the second best answer. They have moved to areas otherwise they couldn't come back. The only problem is claiming the new land. If they did that, why would they come back?
I still think it is A, but don't be surprised if the answer turns out to be D.
