What cause reponse to an increase in the number of immigrants in the early nineteenth century

Job Availability In United States

Explanation:

United States implemented the use of technologies from the Industrial Revolution during early nineteenth century. This created a lot of job opportunities for the people around the world.

This led to a large scale immigration from around the world to United States / Especially from the countries that haven't undergone the industrial revolution during that time such as Countries form Southern Europe and countries form Asia.

answer; higher rate;

answer; adoption agencies tend to place separated twins in similar homes;