Out of the following, poor immigrants were found in slums that are developed in large American cities in the late 1800's.
<u>Explanation:</u>
There were places in the United States that were once slums but with the advent of industrialisation, the same slums grew into large and developed cities.
These slums were originally inhabited by poor immigrants but as the employment opportunities multiplied rapidly, prosperity automatically fled these slums and its inhabitants no longer stood poor.