This is a personal question, so answer how you personally feel.
Answer: D) The use of the domesticated horse in hunting and warfare.
Explanation:
With horses now domesticated, the Indians could travel so much further than before which led to them being able to hunt animals more effectively in many parts of the land.
The Indians also used the horses in warfare as some of them got so adept at using horses that they developed astonishing qualities which they then used to expand their territories against weaker tribes.
The growth of American cities during the late 19th and early 20th centuries led progressive reformers to push for "improved public services" although many pushed for women's rights as well.
Presidents role as Chief legislator
Mobilization, the action of a country or its government preparing and organizing troops for active service
