<span>George McClellan was the democratic candidate, to whom ran against the renown Republican candidate, Abraham Lincoln.</span>
The answer to this question is: NAPOLEON
I think, that the answer to why, is that the change in presidencies from republican to democratic (i might be wrong, and it could be democratic to republican) influenced the change slightly because the new party, wanted to focus on different issues such as westward expansion. As to how, it was because the government withdrew all federal troops from the south, so there wasn't anybody to enforce the laws protecting African American rights so the southerners were free to exploit the African Americans to their will.
The Mayan pyramids and temples were made by bricks and covered by limestone.
I believe the answer is A: Roman Emperors Through History because it was printed in 1721, the only book on the list not published after 1800.
Hope this helps!