In what present day state was most of the land ceded by the Native Americans in the Treaty of Greenville

The correct answer is Ohio.

The treaty of Greenvile was signed at Fort Greenvile in what is present day Greenvile, OH. It ended the Northwest Indian War. William Henry Harrison, who would one day become President, was a representative of the US Government at the negotiations of the treaty and would go on to become Governor of the newly formed Indiana.