Answer:
The correct answer is:
one-party system
Communist
atheist
Step-by-step explanation:
The Soviet Union was under the Communist regime, which refers to the one-party system. The Communist Party was founded in 1912 by Vladimir Lenin and it was the only governing party of the Soviet Union. They did not admit any religion and propagated exclusively the atheism, as they had an ideological goal to eliminate the religion from the Soviet Union.
On the other hand, America was a federal republic with a multi-party system and freedom of speech and elections. Also, America admitted Judeo-Christian values and communities as an integral part of American society.