<span>the correct option is C
</span><span>borders created by imperialist nations have led to modern ethnic tensions
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Modern ethnic tensions were caused by the scramble for and partition of the various spheres of influence often putting often hostile communities into one border, or separating these communities into different states, therefore diminishing their political importance.
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The term muckraker<span> was used in the </span>Progressive Era<span> to characterize reform-minded American journalists who attacked established institutions and leaders as corrupt. They typically had large audiences in some popular magazines. In the US, the modern term is </span>investigative journalism<span> — it has different and more pejorative connotations in British English
</span><span>The muckrakers played a highly visible role during the Progressive Era period, 1890s–1920s</span>
a) hunter gatherers who built mounds
The various cultures collectively termed "Mound Builders" were inhabitants of North America who, during a circa 5,000-year period, constructed various styles of earthen mounds for religious, ceremonial, burial, and elite residential purposes.
