Read the passage below and answer the question."as available resources increased, societies had to face, for the first time, the task of dealing with surpluses, whose control and distribution posed entirely novel problems. and, surprisingly quickly, their distribution became lopsided, so that gradients of power and wealth appeared. surpluses began to sustain populations of privileged (and mainly male) specialists: artisans, traders, warriors, priests, scribes, and rulers. it is worth noting how paradoxical this steepening of hierarchies is. for the increases in productivity associated with the agrarian revolution might, in principle, have raised the average material living standards of all members of society. the reality was different. unlike water, which prefers to lie flat as it accumulates, material wealth in complex societies likes to pile itself up into huge pyramids."from david christian, maps of time: an introduction to big history (2004).what does the author argue that resource surpluses caused? a. resource surpluses caused different levels of social status to emergeb. resource surpluses raised the standard of living of all citizens, but more for some groups than othersc. resource surpluses resulted in the emergence of city states. d. resource surpluses gave increased power and wealth to the laborers who grew the food.