In the Chesapeake region, slavery: a. rapidly became the dominant labor system after 1680. b. was geographically restricted to the Tidewater area until transportation improved in the nineteenth century. c. allowed planters to make vast profits from cotton and rice as well as from tobacco. d. was so widely practiced that nearly three-fifths of white households in 1770 included a slaveowner. e. was the labor system preferred by planters as early as the 1620s.