TOEFL Reading: ETS-TOEFL阅读机经 - LRUA5B84QDA17D7QL$

According to paragraph 3, which of the following was a disadvantage of aggregation? A. People lived farther from the fields in which they worked. B. Facilities for food processing and food storage became inadequate. C. Cooperation between the various groups in the management of labor pools became difficult to maintain. D. Networks set up to facilitate trade between the larger villages broke down over time.