what marked the end of the russian monarchy?\nthe russian civil war\nthe russian revolution\nthe tsar and…

Brief Explanations:

The Russian Revolution led to the overthrow of the Tsarist autocracy. While the execution of the tsar and his family (which occurred after the revolution) was a significant event related to the end of the monarchy, the revolution itself was the event that fundamentally marked the end of the Russian monarchy. The Russian Civil War was a conflict that followed the revolution. The tsar and his family's move to Siberia was a consequence during the revolutionary upheaval but not the event that marked the end of the monarchy.

Answer:

the Russian Revolution