Which best describes the social development of early mesopotamian civilization? a. communal farming, including the operation of sophisticated irrigation systems, led to egalitarian communities without clear social divisions. b. surplus farming, through the operation of irrigation systems, led to the rise of a powerful ruling merchant class elite. c. successful operation of irrigation systems led to the rise of cities, specialization of labor, centralization of power, and class divisions. d. operation of a community’s irrigation system was led by its religious leader, creating a ruling class of priests who oversaw all other social divisions.