Why did the u s encourage immigration during late 1800s

Well, there are a few reasons behind this-

Europe- Had become over-crowded, so they started going into the U.S .

The Industrial Revolution- This also sparked the beginning of encouraging immigrants. Cheaper supplies were made by factories at mass amounts in less time than by one person's hand.

Religion and political chaos- Was starting to rise in Norway and Germany, With the churches causing harassment, forcing them to come into the U.S, trying to get away.

The German Revolution- Sent people from Germany into the U.S, since it didn't really work out.

Freedom- Also a main factor in this. Because the U.S allowed people to practice whatever they desired.

Economic Opportunity- Immigrants came for a better life.

Plentiful Land- The Louisiana Purchase and Mexican Cession's effect on the U.S had gained more than enough land, so this attracted Europeans who had faced overcrowding  in their country.

And this had sparked encouragement for Immigrants in the U.S.

I'm honestly hoping this helps you out..!

the real answer is b

by improved communication.