Answer:
B. decreased Cold War tensions because people felt safe from nuclear attack on their homelands
Explanation:
"The war is won," he said in December 1945, "but the peace is not." The development of the atomic bomb and the subsequent arms race between the United States and the Soviet Union ushered in a new conflict: the Cold War. Einstein feared this battle would end with the destruction of civilization.
<span>Westward Expansion and the American Civil War. To many nineteenth century Americans, the expansion of slavery into Western territories caused a great deal of controversy. ... These fears were realized when the expansion of slavery into western territories entered Congressional debates</span>
4. Groups advocated safer working conditions for factory workers.