The statement that describes the Plains Indians correctly is:
They spoke different languages but were able to communicate through sign language.
This statement reflects the linguistic diversity among various Plains Indian tribes and their use of a common sign language for communication between different groups.
The other statements are not entirely accurate:
- While some Plains Indians practiced agriculture, many were primarily nomadic and relied heavily on buffalo hunting for their food, clothing, and tools.
- Many Plains Indians were still living in their traditional territories at the time settlers moved west, and the reservation system was established later.
- Plains Indian tribes were diverse and had different lifestyles, and while there were common spiritual beliefs, they did not all practice the same religion.