In the Biocultural Connection section, how do Ramenofsky and Galloway explain the disappearance of Native American populations between the explorations of Hernando de Soto and the later arrival of French explorers along the Mississippi?

a. They argue that Hernando de Soto's runaway pigs carried diseases that infected the local fauna and food source for the Native American of that region. b. They argue that Hernando de Soto's army carried diseases that spread to the Native Americans of that region. c. They argue that the Native Americans were nomadic and moved to another region by the time the French explorers arrived. d. They argue that Native Americans never lived in that region and the sites they found were ceremonial centers visited infrequently.