OG4 阅读 Q17

Choice C is the best answer. In lines 66-71("Virtually ... continuum"), the author provides evidence that American cities in 1974 had a 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 residen-tial suburbs for the wealthy and the upper middle class at the far end of the continuum."
Choices A, B, and D are incorrect because they do not provide evidence that American urban cities in 1974 had a traditional four-zone structure. Choice A references a seminal paper on the layout of American cities, choice B identifies Burgess's original theory, and choice D focuses on movement to the suburbs.