At the conclusion of the Russian Civil War, Russia was recognized as the first Communist country in
the world. What was the name of this new Communist country?
A) Union of Communist States (U. C.S.)
B) Soviet Union
C) Union of Soviet Socialist Republics (U. S.S. R.)
D) Both B and C

The answer is C) Union of Soviet Socialist Republics (U.S.S.R.)

Explanation:

And the end of the Russian Civil war, also known as the red October revolution, The Bolsheviks, led by V. I. Lenin, successfully ended the reign of Tsar Nicholas 2 and established the 1st communist state in the world.

This union of nations included Russia along with dozens of central asian and eastern european nations.

and until his death in 1924, Lenin led the nation.  

the answer would be a).