OG4 阅读 Q16

Choice C is the best answer. The author explains how sociologist Ernest W. Burgess determined that urban areas have a traditional four-zone structure (lines 54-63,"Much of... dwellings"). He then states that Burgess was "right about the urban America of 1974" (line 65,"he... of 1974") as it also followed the traditional four-zone structure: "Virtually every city in the country had a downtown, where the commercial life of the metropolis was conducted; it had a factory district just beyond; it had districts of working-class residences just beyond that; and it had residential suburbs for the wealthy and the upper middle class at the far end of the continuum" (lines 66-71,"Virtually... continuum").
Choices A, B, and D are incorrect because the passage does not imply that American cities in 1974 were witnessing the flight of minority populations to the suburbs, had begun to lose their manufacturing sectors, or were already experiencing demographic inversion.