Answer:
Martov
Step-by-step explanation:
In 1903, two factions emerged after a dispute in the Russian Social Democratic Labour Party (RSDLP). This conflict involved Julius Martov and Vladimir Lenin. As the conflict became more intense, the Congress divided into the Mensheviks (minority), who were led by Martov and the Bolsheviks (majority) who were led by Lenin. Although their differences were very small, the most significant one was that the Mensheviks tended to be more moderate.