Why were the "new" immigrants unable to blend into american society as easily as the "old" immigrants who had come before them?

The "new" immigrants unable to blend into American society as easily as the "old" immigrants who had come before them because they did not run through the same religion as most Americans. The "new" immigrants signify a risk to nativist Americans because their cultures and languages were unacquainted to nativist Americans.

the answer is d.index