During the Industrial Age, millions of immigrants entered the United States, significantly impacting its demographics and economy. This period saw over 30 million newcomers, primarily from Europe, driven by the search for economic opportunities. The influx helped shape urbanization and the development of American industry. ;
During the Industrial Age, millions of immigrants entered the United States, primarily from Europe, due to the search for economic opportunities and a better life. Over 30 million immigrants arrived between 1820 and 1930, significantly impacting the country's demographics and society. Therefore, the correct answer is C. millions.
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