Final answer:
Option (1), The farmers who moved to the American Great Plains and used modern farm machinery to cultivate the land were called homesteaders, who were part of the westward expansion inspired by Manifest Destiny and aided by the Homestead Act of 1862.
Step-by-step explanation:
The individuals who moved to the American Great Plains and utilized modern farm machines to make the region productive for agriculture were known as homesteaders. These pioneers took advantage of the Homestead Act of 1862, which offered them land to start their own farms, with the stipulation that they live on and cultivate the land for a period of time. Despite the challenges they faced, such as harsh weather conditions and arid land, these settlers embodied the spirit of American expansion and the belief in Manifest Destiny.
These homesteaders were distinct from other groups who moved west for different reasons, such as those involved in mining or cattle, who were seen as a different breed of settler. The homesteaders' life on the frontier was tough, often requiring innovative farming techniques like dry-farming and, later on, the utilization of irrigation systems post the passage of the Newlands Reclamation Act in 1902. Small family farms had to work hard to survive, many using scales of economy to turn a profit, whereas others, unable to sustain their livelihoods, eventually became disillusioned and left, as seen in the case of the 'Okies' during the 'dirty thirties'.