Final answer:
The purpose of the passage is to show how quickly cities grew after 1860 due to immigration, migration, and industrialization.
Step-by-step explanation:
The purpose of the passage is not clearly stated in the options provided. However, based on the information in the passage, the best description of the purpose of the passage would be Option C - to show how quickly cities grew after 1860 due to immigration, migration and industrialization.
The passage provides information about the population growth and urbanization of cities like New York City, Chicago, and Philadelphia during a specific time period. It also highlights the factors that led to this growth, such as immigration, migration, and industrialization. Overall, the passage focuses on the rapid expansion and changes in cities during this time.