Examine the following map showing the Olmec heartland and the southern Maya empire. Based on the map, which of the following statements is most likely true? A. The Maya and the Olmec frequently traded with each other. B. Olmec land was agriculturally richer than the land of the southern Maya. C. The Maya were more successful than the Olmec in their conquests. D. The Olmec established a foundation for the Maya civilization.