A. prove that the city refused to deal with pollution B. prove that medical science once knew little about pollution C. introduce the idea of contaminated water supplies D. recall a historical fact 参考答案:C 答案解析:此题为细节题。答案在第一段。线索词为“London cholera”。此题考查作者引用的目的。A项与文中所述事实相反。B项文中未涉及此话题。D项“London cholera”是一个“hist