Immigration was certainly a key factor in the growth of America's economy . The Industrial Revolution came with massive technological developments, and the chance to exponentially improve the production rate of factories. However, to operate these emerging industries it would take a tremendous amount of laborers. American citizens working alone, weren't going to be enough. In other words, the peak of immigration influx allowed the U.S. to take full advantage of the possibility at the right time.
Hope this helps!
Answer:
The correct answer is the first one.
I would say A, they were very resourceful. Hope this helps.
