Task: Question Answering
Input (English): Passage: Born at Podolskaya Street in Saint Petersburg, Russia, Shostakovich was the second of three children of Dmitri Boleslavovich Shostakovich and Sofiya Vasilievna Kokoulina. Shostakovich's paternal grandfather, originally surnamed Szostakowicz, was of Polish Roman Catholic descent (his family roots trace to the region of the town of Vileyka in today's Belarus), but his immediate forebears came from Siberia. A Polish revolutionary in the January Uprising of 1863–4, Bolesław Szostakowicz would be exiled to Narym (near Tomsk) in 1866 in the crackdown that followed Dmitri Karakozov's assassination attempt on Tsar Alexander II. When his term of exile ended, Szostakowicz decided to remain in Siberia. He eventually became a successful banker in Irkutsk and raised a large family. His son Dmitri Boleslavovich Shostakovich, the composer's father, was born in exile in Narim in 1875 and studied physics and mathematics in Saint Petersburg University, graduating in 1899. He then went to work as an engineer under Dmitri Mendeleev at the Bureau of Weights and Measures in Saint Petersburg. In 1903 he married another Siberian transplant to the capital, Sofiya Vasilievna Kokoulina, one of six children born to a Russian Siberian native.Their son, Dmitri Dmitriyevich Shostakovich, displayed significant musical talent after he began piano lessons with his mother at the age of nine. On several occasions he displayed a remarkable ability to remember what his mother had played at the previous lesson, and would get "caught in the act" of playing the previous lesson's music while pretending to read different music placed in front of him. In 1918 he wrote a funeral march in memory of two leaders of the Kadet party, murdered by Bolshevik sailors.In 1919, at the age of 13, he was admitted to the Petrograd Conservatory, then headed by Alexander Glazunov, who monitored Shostakovich's progress closely and promoted him. Shostakovich studied piano with Leonid Nikolayev after a year in the class of Elena Rozanova, composition with Maximilian Steinberg, and counterpoint and fugue with Nikolay Sokolov, with whom he became friends. Shostakovich also attended Alexander Ossovsky's music history classes. Steinberg tried to guide Shostakovich on the path of the great Russian composers, but was disappointed to see him 'wasting' his talent and imitating Igor Stravinsky and Sergei Prokofiev. Shostakovich also suffered for his perceived lack of political zeal, and initially failed his exam in Marxist methodology in 1926. His first major musical achievement was the First Symphony (premiered 1926), written as his graduation piece at the age of 19. This work brought him to the attention of Mikhail Tukhachevsky, who helped Shostakovich find accommodation and work in Moscow, and sent a driver around in "a very stylish automobile" to take him to a concert. 
Question: What was the last of Dmitri Dmitriyevich Shostakovich's mother?
Output (English): Kokoulina.