<span>Iran hostage crisis, panama canal treaty
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Definitely C! The efforts of Martin Luther King Jr resulted in great political change.
They perchased the land from mexico which included everything west of the Mississippi River
Answer: The Industrial Revolution.
Explanation:
The industrial revolution fundamentally changed everyday life. People began to leave the rural areas of the country en masse and move to the cities. Cities are becoming centers of life and places where industrial plants are installed. A large number of people are moving to cities for better opportunities. The industrial revolution had its phases in the twentieth century as well, so that process continued in that period. Thus, the economic factors of this phenomenon are in the background.