Answer:
In the nation's growing cities, factory output grew, small businesses flourished, and incomes rose. As the promise of jobs and higher wages attracted more and more people into the cities, the U.S. began to shift to a nation of city dwellers.
Explanation:
Because door of world is open for all..
and so U.S entered WW1
I believe it was the 15th century
C. The Buddha
The Buddha was the leader