This russian social democratic group was led by lenin, who wanted only single-minded, loyal revolutionaries in his organization

The correct answer is A) Bolsheviks.

The other options of the question were B) Proletarians. C) Populists. D) Mensheviks.

This Russian Social Democratic group was led by Lenin were the Bolsheviks.

Vladimir Lenin led the Bolsheviks to revolt against the Russian government in 1917.  He became the leader of Russi, in what represented the first Communist country in the world. That is when the Russian territory adopted the name of the USSR or Union of Soviet Socialists Republics. As the ruler of the USSR, Lenin nationalized the industry in the country and split the land.