In the thirteenth century, the people in the Mesa Verde area went from living in scattered independent households to living in large pueblos. A. Because the thirteenth-century inhabitants of the Mesa Verde area did not have the cultural expectations of today's city dwellers, they easily adapted to communal life. B. Even though living in pueblos had disadvantages, the population of the area had grown so large that there may have been no other arrangement that would have met its needs. C. From the eleventh century onward, farmers began to increase food production on existing farmland and started bringing more land under cultivation. D. A development that contributed to increasing population densities was a cooling climate that led many people to leave the coldest areas and crowd into climatically more favorable areas. E. The primary reason for moving to pueblos was the social benefits associated with communal life. F. People were brought together by the need to produce food cooperatively, as the use of food surpluses in one place to relieve shortages in another ended due to a change in climate.