During the early 20th century, increased immigration, industrialization, and urbanization led

a) a period of economic recession and high unemployment rates.
b) a period of considerable economic growth in the united states.
c) increased american expansion overseas to secure natural resources.
d) increased warfare against the native americans on the western frontier.

B) a period of considerable economic growth in the United States.
Because industry grew up along rivers in cities, which led to rapid urban development. People from the countryside relocated to the cities looking for jobs and better economic opportunites. As cities grew in poulation, this fed the need for more urban development, which led to further industrialization, and more jobs in turn, leading to a continued cycle of growth.