Which of the following best explains why US cities became segregated by culture and ethnicity in the late 1800s and early 1900s?

Immigrants often settled near people who shared their language, culture, or country of origin. These communities offered social support, familiar customs, and help finding work, especially when immigrants faced discrimination or exclusion elsewhere. City planners and government authorities generally did not officially assign ethnic groups to neighborhoods, so A is the best explanation.

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