The changes in the patterns of immigration during the last 40 years illustrate the fact that the population of the united states is becoming much more

Hetergeneous

Explanation:

A population or society is said to be heterogeneous when that population or society is consists of different kinds of people from all walks of life for various reason.

For the few past years, different people of diverse belief system, culture, nationality, etc. have migrated and are still migrating to the US

"social stratification refers to the way people are ranked and ordered in society. in western societies, stratification is primarily seen and understood as a result of socioeconomic status, which produces a hierarchy in which access to resources, and possession of them, increases from the lower to the upper strata"

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