Final answer:
Industrialization surged in late 19th-century America due to immigration and urbanization, which created a large pool of cheap labor and, coupled with technological advances, led to continuous factory operations.
Step-by-step explanation:
The industrialization increased dramatically in the United States during the late nineteenth century primarily because of immigration and urbanization, which provided a surplus of cheap labor. This influx of workers, coming from both rural areas within the United States and from many parts of Europe and other regions of the world, fueled the expansion of industrial employment opportunities. Additionally, technological advancements such as electric lights and powered machinery enabled factories to operate continuously, further increasing the demand for labor.