please help...
After the United States government targeted the buffalo wiping out the Plains tribes' main food supply

A) most of the surviving Plains’ tribes were forced to live on reservations, while some American tribes escaped to Canada

B) the Plains’ tribes made a final stand at the Battle of Little Big Horn

C) the Plains’ tribes resorted to new farming techniques to survive

D) the Plains’ tribes made an alliance with Britain and France starting the Great Sioux War