Question: Are Sergei Prokofiev and Modest Mussorgsky both Soviet composers?
Sentence (from "Sergei Prokofiev"): Sergei Sergeyevich Prokofiev ( ; Russian: Сергей Сергеевич Прокофьев , "Sergej Sergejevič Prokofjev" ; 27 April 1891 – 5 March 1953) was a Soviet composer, pianist and conductor.
Relevant evidence: Yes