What happened in the Sand Creek Massacre? A. Cheyenne Indians attacked white settlers, leading to war.
B. American Indians killed pioneers on the Oregon Trail, which led to the construction of the Transcontinental Railroad.
C. U. S. soldiers in Colorado attacked a village of American Indians who had been promised protection.
D. Free African Americans and American Indians fought together against white settlers.

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Explanation:

At dawn on November 29, 1864, approximately 675 U.S. volunteer soldiers commanded by Colonel John M. Chivington attacked a village of about 750 Cheyenne and Arapaho Indians along Sand Creek in southeastern Colorado Territory. Using small arms and howitzer fire, the troops drove the people out of their camp.it´s A.

Explanation:

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