Question

Which of the following was a cause of the increase in total U.S. urban population during the early 20th century?

Answer 1

Answer: Job opportunities in industry.

Explanation:

The urban population had been growing steadily since the end of the Civil War, getting the United States to be the country with the largest cities in the world.  Economic changes and technological progress developed an industry that required workers moving into the new cities. According to the 1920 United States´ census, by then the population in urban areas had surpassed those in rural areas.  

Answer 2

I think it would be the new job opportunities but they were still dirty, yes labor unions existed but worked elsewhere