Why Was the Battle at the Little Bighorn River in 1876

Why was the battle at the Little Bighorn River in 1876 significant?

A) General George Custer's troops defeated the Cherokee and Seminole Indians, leading to greater prosperity for the Native Americans on the Dakota Reservation.
B) Thousands of Indians led by Crazy Horse annihilated a detachment of Custer's soldiers, leading Congress to prepare for "total war."
C) Although Chief Red Cloud was captured and murdered, his death boosted Sioux morale and ensured they would win the war.
D) Sioux and Cheyenne Indians won a large chunk of the Montana Territory, which they kept for fourteen years.
E) Chief Sitting Bull scouted for the United States against his own people because Grant and Congress promised to establish a peace policy.