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.

可进行骨髓移植治疗的贫血是

A．巨幼细胞性贫血

B．再生障碍性贫血

C．自身免疫性溶血性贫血

D．慢性病贫血

E．缺铁性贫血