Answer:
25 million.
Step-by-step explanation:
Industrial revolution can be defined as a period of significant change in economic and social manufacturing process characterized by the use of handicrafts and agrarian methods to the use of power-driven equipments and machines. Basically, the industrial revolution began in Great Britain (England) between 1760 to 1840 and eventually spread across other countries of the world.
Migration refers to the movement of a group of people from one geographical region (location) to another geographical destination in search of better living conditions, work or social amenities.
Migration selectivity can be defined as the likelihood or tendency that a subset (part) of a group of people are going to move (migrate) out of a particular geographical location or area.
Some of the factors that influence migration selectivity are income level, age, education, gender etc.
Between 1870 and 1916 during the industrialization period, approximately 25 million immigrants came to the United States of America in search of greener pastures and better living conditions or standard of living.