Which best completes the diagram?

Here are some possibilities:

The U.S. entered World War I because Germany embarked on a deadly gamble. Germany sank many American merchant ships around the British Isles which prompted the American entry into the war.

Explanation:

while it was true that the cotton gin reduced the labor of removing seeds, it did not reduce the need for slaves to grow and pick the cotton.

explanation:

before eli whitney's invention of the cotton gin, picking and cleaning cotton was a slow, labor-intensive job. workers, usually slaves, had to pick the seeds from the cotton fibers by hand. this invention made it possible to grow large amounts of cotton on big farms and make money.

the main objectives of the progressive movement were eliminating problems caused by industrialization, urbanization, immigration, and political corruption.