Climate changed colder and wetter,people weakened by hunger and were led to diseases
Your answer is A, Conflict with Native Americans ended.
Louisiana purchase entailed negative consequences for most of the Louisiana population - blacks and Indians - and became one of the causes of acute social contradictions in modern America. In just 30 years, Americans ousted Indians from most of the Mississippi Valley, physically destroying or expelling them from their ancestral lands through fraudulent treaties
Genghis Khan forged the initial Mongol Empire in Central Asia, starting with the unification of the Mongol and Turkic confederations such as Merkits, Tartars, and Mongols
Totalitarianism is a form of government in which the national government takes control of all aspects of both public and private life, often led by a charismatic leader and only one party. To control their populations, these governments often employed:
Rule through fear
Censorship of media
Propaganda in media,
government speeches and through education
Criticism of the state is prohibited
Mandatory military sign up
Secret police forces
Controlling reproduction of the population
Targeting of specific religious or political populations
C) Extinction can be caused by human induced activities or natural activities
An example of natural activities causing extinction is the extinction of the dinosaurs and example of human activities causing extinction is deforestation.
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