Question

which development completes the diagram?
decline in u.s. economic growth
migration of industrial workers to farms
decreasing numbers of monopolies
second industrial revolution

Explanation:

The Bessemer process (steel production), improvements in communications (like the telegraph), spread of railroads, and rise of oil and electricity industries are all key elements of the Second Industrial Revolution. The Second Industrial Revolution was a period of rapid industrialization. The decline in U.S. economic growth is incorrect as the Second Industrial Revolution spurred economic growth. Migration of industrial workers to farms is wrong as industrialization led people to move to cities for factory jobs. Decreasing numbers of monopolies is incorrect as monopolies like those of Rockefeller (oil) and Carnegie (steel) were prominent during this time.

Answer:

Second Industrial Revolution