By the sixteenth century, the Incas of South America ruled an empire that extended along the Pacific coast and Andean highlands from what is now Ecuador to central Chile

This strategy of direct access to a maximum number of ecological zones by a single group is called vertical economy. Even today, one can see Andean communities maintaining use rights simultaneously to pasturelands above 12,000 feet, to potato fields in basins over 9,000 feet, and to plots of warm-land crops in regions below 6,000 feet.This strategy has two principal variations.
The first is “compressed verticality,” in which a single village resides in a location that permits easy access to closely located ecological zones. Different crop zones or pasturelands are located within a few days walk of the parent community. Community members may reside temporarily in one of the lower zones to manage the extraction of products unavailable in the homeland. In the second variation, called the “vertical archipelago,” the village exploits resources in widely dispersed locations, constituting a series of independent production “islands.” In certain pre-Columbian Inca societies, groups were sent from the home territory to establish permanent satellite communities or colonies in distant tropical forests or coastal locations. There the colonists grew crops and extracted products for their own use and for transshipment back to their high-altitude compatriots. In contrast to the compressed verticality system, in this system, commodities rather than people circulated through the archipelago.
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According to the passage, the inhabitants of the Andean highlands resolved the problem of unequal resource distribution primarily in which of the following ways?

According to the passage, the inhabitants of the Andean highlands resolved the problem of unequal resource distribution primarily in which of the following ways?

A.Following self-sufficient agricultural practices

B.Increasing commodity production from the ecological zones in the highland basins

C.Increasing their reliance on long-distance trade networks

D.Establishing satellite communities throughout the Andean highlands

E.Establishing production forces in ecological zones beyond their parent communities

选E，是在红色部位定位吗？为什么不选A呢？aotonomous不就是self-sufficient吗~？E中的parent哪里提到了呀