in 1866 Chief cloud ambushed and massacre Union soldiers the massacre was named what A. Little big horn B.Wounded Knee C.Fetterman D. Chivrington

Fetterman massacre.

In December 1866, the Native American allies attacked and defeated a United States unit in what the whites would call the Fetterman Massacre (or the Battle of the Hundred Slain), which resulted in the most U.S. casualties of any Plains battle up to that point.

http://en.wikipedia.org/wiki/Red_Cloud

Thxs so much

The correct answer is C. Fetterman.

To find this answer, one could start by researching events related to Native American attacks on Union soldiers during the time period of 1866. Chief Cloud, also known as Chief Red Cloud, was a prominent Native American leader of the Lakota Sioux during the 19th century. In the year 1866, Chief Red Cloud's forces ambushed and massacred Union soldiers in a battle that came to be known as the Fetterman Massacre.

Further research on the Fetterman Massacre would provide more details about the event, such as the location, the number of casualties, and the historical significance of the battle.