Answer:
The right answer is Nihilists and Communists.
Step-by-step explanation:
Nihilists were a secretive organization acting in the second half of 19th century; their most well-known act was the assasination of Tsar Alexander II in 1881. On the other hand, the Bolsheviks were for a long time an underground group in the Russia of the early 20th century; they later called themselves Communists after their consolidation in power.