At the end of the Ice Age, patterns of human settlement changed in southwestern Asia. A. Wild cereals, grasses, and nuts were exchanged for exotic objects. B. Changes in climatic conditions made southwestern Asia highly beneficial to human occupants. C. Social organization in Abu Hureyra decreased as the population grew. D. The favorable location of Abu Hureyra kept the city from experiencing hardship during drought years. E. Within 2,000 years, populations in southwestern Asia greatly increased in number.\ F. In rich, fertile areas permanent societies evolved to a high level of complexity.