问题
单项选择题
According to the passage, what is a megapolis
A．One of the 10 largest cities in the United States.
B．One of the 18 largest cities in the United States.
C．One of thel00 cities between Boston and Washington.
D．Any number of continuous adjacent cities and suburbs.
答案
参考答案：D
解析：[分析] 细节题型。 答案出自第四段第二句In addition, the Bureau recognizes 18 megapolises, that is, continuous adjacent metropolitan areas．