They addressed issues that led to the Civil War. The 13th, 14th, and 15th amendments were known as the Civil War Amendments, and were made to ensure equality for recently emancipated slaves. Because slavery led to the Civil War, the answer is C.
Christianity has promoted a sense of understanding and a common ground in society, and because of this understanding the chances of unnecessary wars and violence have been reduced.
Since the Muslims were the once attached (by the Christians) their action was mostly to respond and defend themselves; rather than undertake other initiatives.
The Crusades have caused the Muslims to unite more, but generally their reaction was very weak and not long-lasting.
I would say communism ☆〜（ゝ。∂）
Explanation:
Social Darwinists believe in “survival of the fittest”—the idea that certain people become powerful in society because they are innately better. Social Darwinism has been used to justify imperialism, racism, eugenics and social inequality at various times over the past century and a half.
