The increasing diversity of the American workforce, and the fact that people aged 18–34 are more likely to be living with their parents than with a spouse or partner, are both examples of a(n) force for change.

Demographic

Explanation:

Factor such as fertility, migration and mortality determine the distribution and composition of population in any society which is called demography. It is observed that demographic population collectively exhibits certain characteristic which defines them in the society which they live.

In the problem mentioned, the increased diversity of american workforce between age 18 to 34 have started leaving with their parents. It shows collective behavior characteristic of the American Workforce and hence it is an example of Demographic force for change.  

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