One effect of the rise of mass culture across the united states in the 1920s was that it

allowed americans across the country to share common experiences.

diverted attention from politics to entertainment.

americans preserve regional differences and traditions.

emphasized the difference between country and city life.

Hi, we can say;

It allowed Americans across the country to share common experiences

Explanation:

Mass culture was a new movement in 1920s that emerged in the United States facilitated by movie production in Hollywood, popularity of sport games and increased advertisement that targeted the entertainment industry.For example movies and radios created a homogeneous society.Non-Americans assimilated to American society faster due to mass culture which helped to eliminate regional differences.More Americans lived in the city compared to those in farms.There was a wave of change across the whole nation.

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