B. It gave the ability to purchase surplus lands
<span><span>Pulli settlement in Estonia, 9000 BC
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Spirit Cave in Thailand, 9000–5500 BC</span></span>
Conflicts where the superpowers supported opposing sides but did not confront each other directly.
Rivers, and flat plains.
Rivers proved pivotal for settlements to grow since it provides a means of water for growing crops, a means of produce which people can consume. Rivers also are a means of transportation and a geographic barrier against attack, albeit slight.
Flat plains also proved viable for settlements because of how easy they were to traverse, coupled with it being easier to farm on said land.
