TOEFL Reading: ETS-TOEFL阅读机经 - YJMB2A0MJ55918E1L$

According to paragraph 3, why did the apparent advantages of larger settlements in fact lead to the failure of the Anasazi village system? A. The large size of the settlements made improving processing and storage of necessary food difficult. B. The trading networks could no longer support the growing needs of large villages. C. The long-distance hunts that had to be organized took too many resources away from the labor pool. D. The management system the people practiced made it difficult to deal appropriately with periods of bad harvests.