The correct option is "They are the largest tribe in Oklahoma, and they are federally recognized and successful. "
The Cherokee are an indigenous group of North America that inhabited the current territory of the states of Alabama, Georgia, Kentucky, North Carolina, South Carolina, Tennessee and Virginia in the southeastern United States when Europeans contacted them in the 20th century. XVI. Subsequently, most of the Cherokee were forced to move to the Ozark Plateau (Oklahoma). The Cherokee were one of the peoples who grouped themselves in the «Five Civilized Tribes».