Where do most immigrants to the united states come from today?

The United States is a country shaped by immigration, but in many cases throughout its history there has been controversy about newcomers. Today, about 14% of the population of the United States was born abroad. Today, the majority of immigrants in the US they come from Latin America or Asia, a big change from the last century, when most came from Europe.

the answer would be:

b. race

if i am correct the answer is going to be a) the federal program of reconstruction ended.