What is the main idea presented in this passage? Ancestral Puebloans lived in the cliff dwellings [of Mesa Verde] for less than
100 years. By about... 1300, Mesa Verde was deserted. Several theories offer reasons for their migration. We know that the last quarter of the... 1200s saw drought and crop failures-but these people had survived earlier droughts. Maybe after hundreds of years of [overuse], the land and its resources-soils, forests, and animals-were [used up]. Perhaps there were social and political problems, and the people simply looked for new opportunities elsewhere.¹ A. The farming techniques used by Ancestral Puebloans were harmful to their land. B. There are many reasons why the Ancestral Puebloans may have left Mesa Verde. OC. The Ancestral Puebloans often dealt with droughts and environmental problems. D. The Ancestral Puebloans had to leave Mesa Verde due to polial problems.