The correct answer is - trade.
The Sumerians engaged in trade with their move of exchanging their surplus food for materials like the copper that they needed to develop their weapons and thus their army forces. This was a very smart move from their side because they managed to use the resource they had in abundance but was scarce in the other surrounding areas so that they take what they need to become stronger and pretty much defend more efficiently from the same people they were engaging in trade with.
Its basic cause was a dynastic quarrel that originated when the conquest of England by William of Normandy created a state lying on both sides of the English Channel. In the 14th cent. the English kings held the duchy of Guienne in France; they resented paying homage to the French kings, and they feared the increasing control exerted by the French crown over its great feudal vassals. The immediate causes of the Hundred Years War were the dissatisfaction of Edward III of England with the nonfulfillment by Philip VI of France of his pledges to restore a part of Guienne taken by Charles IV; the English attempts to control Flanders, an important market for English wool and a source of cloth; and Philip's support of Scotland against England.
Answer:
Confirmation Bias
Explanation:
Confirmation bias is a phenomenon wherein decision makers have been shown to actively seek out and assign more weight to evidence that confirms their hypothesis, and ignore or underweigh evidence that could disconfirm their hypothesis. As such, it can be thought of as a form of selection bias in collecting evidence. Confirmation bias is important because it may lead people to hold strongly to false beliefs or to give more weight to information that supports their beliefs than is warranted by the evidence.