题目解析:
题干提问“在苏美尔文明时期,西南亚社会和科技发展的原因之一是什么”。
定位第1段第4句,social developments and technological innovations were triggered by中的were triggered by为“由…引起”,by后为原因,根据not only … but also …得知其后两个原因:(1)basic economic needs,(2)the competitive instincts of newly urbanized elites, who used lavish display and exotic luxuries to reaffirm their social prestige and authority。(2)可对应C选项,competition = competitive instincts,for prestige and authority = to reaffirm their social prestige and authority。
故选C。