Why was the Industrial Revolution one of the most important developments in human history, and why did it happen so quickly?

What was one major difference between benito mussolini and adolph hitler? o a. hitler was more willing to use violence to secure power than mussolini. o b. hitler made racism central to his political ideology earlier than mussolini. o c. hitler was more supportive of communism and socialism than mussolini. o d. hitler followed the philosophy of militarism more strictly than mussolini.