Why were the yazoo lands so controversial?

Georgia politicians sold large tracts of territory in the Yazoo lands, in what are now portions of the present-day states of Alabama and Mississippi, to political insiders at very low prices in 1794. Although, the law enabling the sales was overturned by reformers the following year, its ability to do so was challenged in the courts, eventually reaching the US Supreme Court. In the landmark decision in Fletcher v. Peck (1810), the Court ruled that the contracts were binding and the state could not retroactively invalidate the earlier land sales. It was one of the first times the Supreme Court had overturned a state law, and it justified many claims for those lands.

Some of the lands sold by the state in 1794 had been shortly thereafter resold to innocent third parties, greatly complicating the litigation. In 1802, because of the ongoing controversy, Georgia ceded all of its claims[2]to lands west of its modern border, to the U.S. government, in exchange for which the government paid cash and assumed the legal liabilities. Claims involving the land purchases were not fully resolved until legislation passed in 1814 established a claims-resolution fund.

The answer is d.  the north had organized schools, whereas the south had few organized schools.