Triple

Target entity: Manifest Destiny
Context triple: [Emigrants Crossing the Plains, theme, Manifest Destiny]

• A. United States territorial expansion chosen
  United States territorial expansion refers to the historical process by which the United States grew from a cluster of Atlantic coast colonies into a transcontinental nation through purchases, wars, treaties, and settlement.
• B. Northern Expansion Doctrine
  The Northern Expansion Doctrine was an Imperial Japanese military and political strategy that advocated expansion into Siberia and the Soviet Far East to secure resources and strategic dominance.
• C. Southern Expansion Doctrine
  The Southern Expansion Doctrine was an early 20th-century Japanese imperialist strategy advocating political, economic, and military expansion into Southeast Asia and the Pacific.
• D. frontier thesis
  The frontier thesis is a theory proposed by historian Frederick Jackson Turner that argues the American frontier experience fundamentally shaped the nation’s democracy, culture, and identity.
• E. Monroe Doctrine
  The Monroe Doctrine was a foundational 19th-century U.S. foreign policy principle that opposed European colonialism in the Americas and asserted a special sphere of influence for the United States in the Western Hemisphere.
• F. None of above.
• G. Unsure - the case is ambiguous/there is not enough information to decide.