Select the correct answer.

why did the united states and the soviets end up on opposite sides of the cold war?
a.
they had been on opposite sides in world war ii and that continued later on.
b.
the united states had the atom bomb and the soviets were not in favor of its use.
c.
the soviets wanted to participate in the marshall plan but were not allowed.
d.
they had very different political philosophies that lead to a deep mistrust of each other.
e.
both wanted control of the oilfields in iran and other middle eastern countries.

What is the main difference between primary and secondary sources? a. primary sources are historical documents, and secondary sources are modern-day documents. b. primary sources are derived from museums and archives, and secondary sources are created by history students and academics. c. primary sources are found in ancient places with a rich history, and secondary sources are found in historical journals and blogs. d. primary sources are created during a particular historical era, and secondary sources are created by studying primary sources.