28. According to the passage, how did the agriculture of the Mississippians differ from that of their Hopewell predecessors?
(A) The Mississippians produced more durable and larger crops of food.
(B) The Mississippians sold their food to other groups.
(C) The Mississippians could only grow plants in warm, dry climates.
(D) The Mississippians produced special foods for their religious leaders.