Which of these changes took place in the first two decades of the 20th century?

a. The United States went from being a net exporter to being a net importer.
b. The industrial workforce went from minority unionized to majority unionized.
c. The majority of the U.S. population lived in urban areas instead of rural areas.
d. The U.S. government moved from running a budget surplus to running a budget deficit.

The majority of the US population lived in urban areas instead of rural areas Hopefully this helps.