9. Which development was responsible for the success of Henry Ford during the early 1900s?

a) the effectiveness of mass production.

Explanation:

Henry Ford was the first car producer (Ford Industries) to use the assembly line, which allowed certain groups of workers to work on specific parts of the car, while simultaneously transferring the component throughout the groups to create a full car at the end. This allowed Ford to create large amounts of cars in short amount of time, decreasing not only cost of production, but also the cost to buy the car, further making the car more popular with the people. This cycle allowed for cheap cars, which in turn made Ford rich.

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