Which piece of evidence in "Immigration and Ellis Island" supports the opinion that Europeans came to the United States primarily to seek economic opportunity?

The author uses as evidence the fact that many immigrants were fleeing poverty in their countries of origin, which presented few job opportunities, unlike the USA.

Explanation:

"Immigration and Ellis Island" shows how, despite the fact that many immigrants in the USA were looking for a way to exercise their religions without suffering persecution, most of them were fleeing poverty and saw in the USA a way to improve their economic conditions. This is because their countries of origin, most of them located in eastern and southern Europe, presented few job opportunities, leaving many of them in a situation of misery. However, the USA had high industrialization and employment opportunities.