Question: What was the nationality of the person who wrote Variations on a Theme by Tchaikovsky?
Sentence (from "Anton Arensky"): Anton Stepanovich Arensky (Russian: Анто́н Степа́нович Аре́нский ; 12 July [O.S. 30 June] 1861 – 25 February [O.S. 12 February] 1906 ), was a Russian composer of Romantic classical music, a pianist and a professor of music.
Relevant evidence: Yes