What was the outcome of the 1917 October Revolution? -Vladimir Lenin was ousted from power.
-It set up a permanent and stable government.
-The Bolsheviks launched a coup d'etat against the government.
-The peasants won and established a democratic government.

Aftermath of the 1917 October Revolution, the Bolsheviks launched a coup d'etat against the government.

The Russian revolution of 1917 is a revolution led by Vladimir Lenin who was Bolshevik Party leader who launched a bloodless coup d'état against the Duma's government in Russia.

Hence, aftermath the 1917 October Revolution, the Bolsheviks launched a coup d'etat against the government.

Therefore, the Option C is correct.

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letter a is the answer