People in the United States moved to cities in the 20th century mainly for employment opportunities and a strong cultural life. Economic activity and vibrant communities attracted many to urban centers. While transportation was a factor, affordable homes and weather were less influential. ;
Historically, people in the United States moved to cities mainly for employment opportunities and a vibrant cultural life. This urban migration was particularly significant during the late 19th and early 20th centuries. Therefore, the correct answer is A. employment and a strong cultural life.
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