Answer:
Settler colonization.
Explanation:
Settler colonialism is a unique form of colonialism that works by replacing indigenous peoples with an invasive settler society, which develops a distinctive identity and sovereignty over time. One of the most striking features is that unlike traders or soldiers, colonizers collectively plan to occupy the indigenous land. The most common examples are nations including the United States, Australia, etc.
Military power and technology.
The population of the west changed drastically during the late 1900s due to improved economic quality, job opportunities, facilities etc. The US government also helped by passing the homestead act in 1862.
With the rising level of economical quality of the west it grew in population due to the large number of immigrants that came for better quality of life and facilities. Also, the rising levels of job opportunities and the cheap cost of living attracted many in need for a better living.
The homestead act passed by the US government in 1862 also helped to increase the heads in the west by offering immigrants 160 acres of land for free. The building of railways also played an important role by improving the transportation facilities and economic developments.
To know more about the homestead act refer to the link below
brainly.com/question/2034839
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Government (a) is the correct answer, also they also provided some education as well
Francisco pizarro overthrew the incas and hernan cortes overthrew the aztecs