Question: The conductor of the first performance of Symphony No. 7 was born in what year?

Context paragraphs:
Symphony No. 1 (Hill): Symphony No. 1 in B-flat major, Stiles 1.3.4.1 Sy1, the so-called Maori Symphony, is the first symphony by Alfred Hill.  Its first three movements were completed by 1898, but the last movement remained unfinished.  This may have been the second symphony composed in the Antipodes (the first was George Marshall-Hall's "C minor" completed in Melbourne in December 1892).  The first two movements (and maybe the fourth, if it was reconstructed correctly) of this symphony are the only symphonic movements by Hill not to be arranged from his earlier chamber music.  The Finale was reconstructed by Allan Stiles, and the whole symphony got its first performance in 2007.  The approximate duration is 40 minutes.

Supplica: Supplica is a short composition for orchestra by the American composer Christopher Rouse.  It was jointly commissioned by the Pittsburgh Symphony Orchestra and the Pacific Symphony.  The first performance of the piece was given in Heinz Hall for the Performing Arts, Pittsburgh by the Pittsburgh Symphony Orchestra under conductor Juraj Valcuha on April 4, 2014.

Symphony No. 7 (Bax): The Symphony No. 7 by Arnold Bax was completed in 1939 and dedicated to "The People of America".  The work received its first performance in Carnegie Hall, New York City, by the New York Philharmonic on 10 June 1939 under the baton of Sir Adrian Boult.  It was commissioned by the British Council to be played at the 1939 New York World's Fair, along with Arthur Bliss's Piano Concerto in B-flat, and Ralph Vaughan Williams' "Five Variants of Dives and Lazarus".

Symphony No. 6 (Vaughan Williams): Ralph Vaughan Williams's Symphony in E minor, published as Symphony No. 6, was composed in 1946–47, during and immediately after World War II.  Dedicated to Michael Mullinar, it was first performed by Sir Adrian Boult and the BBC Symphony Orchestra on 21 April 1948.  Within a year it had received some 100 performances, including the U.S. premiere by the Boston Symphony Orchestra under Serge Koussevitzky on 7 August 1948.  Leopold Stokowski gave the first New York performances the following January with the New York Philharmonic and immediately recorded it, declaring that "this is music that will take its place with the greatest creations of the masters."  However, Vaughan Williams, very nervous about this symphony, threatened several times to tear up the draft.  At the same time, his programme note for the first performance took a defiantly flippant tone.

Symphony No. 12 (Shostakovich): Dmitri Shostakovich composed his Symphony No. 12 in D minor, Op. 112, subtitled "The Year of 1917", in 1961, dedicating it to the memory of Vladimir Lenin, leader of the Bolshevik Revolution, as he did for his Symphony No. 2.  The symphony was premiered that October by the Leningrad Philharmonic Orchestra under conductor Yevgeny Mravinsky.  This was also the last Shostakovich symphony which Mravinsky premiered; his refusal to give the first performance of the Thirteenth Symphony, "Babi Yar", caused a permanent strain in their working relationship.

Symphony No. 4 (Martins): Symphony No. 4, titled Buddha Dharma or rarely Buddha Dhamma was a symphony made by Vasco Martins in 2001.  It was the first fourth symphony made by a Cape Verdean and the fourth symphony made by a Cape Verdean.  The symphony was inspired by reading a book by Buddha.  He composed it slowly (metronome figure circa 45), the one-piece work took two weeks and was made in and around the island of São Vicente.  The first performance was premiered on September 3, 2001 in São Paulo, Brazil by Lutero Rodrigues and the local cultural symphony ("Sinfonia Cultura"), its length is 19-20 minutes.  It was performed in France in 2007 and was done by Henri-Claude Fantapié.  This work can be listened via the MP3 format via the website, this was done by the composer.  The symphony is also available on YouTube.  The work covers around 500 sizes and forms about five crescendos.

Symphony in C (Bizet): The Symphony in C is an early work by the French composer Georges Bizet.  According to "Grove's Dictionary", the symphony "reveals an extraordinarily accomplished talent for a 17-year-old student, in melodic invention, thematic handling and orchestration."  Bizet started work on the symphony in C major on 29 October 1855, four days after turning 17, and finished it roughly a month later.  It was written while he was studying at the Paris Conservatoire under the composer Charles Gounod, and was evidently a student assignment.  Bizet showed no apparent interest in having it performed or published, and the piece was never played in his lifetime.  He used certain material from the symphony in later works, however.  There is no mention of the work in Bizet's letters, and it was unknown to his earlier biographers.  His widow, Geneviève Halévy (1849–1926), gave the manuscript to Reynaldo Hahn, who left it along with other papers to the archives of the conservatory library, where it was found in 1933 by Jean Chantavoine.  Soon thereafter, Bizet's first British biographer Douglas Charles Parker (1885–1970) showed the manuscript to the conductor Felix Weingartner, who led the first performance in Basel, Switzerland, on 26 February 1935.

Symphony No. 7 (Mozart): Symphony No. 7 in D major, K. 45, by Wolfgang Amadeus Mozart, was completed in Vienna in January 1768 after the family's return from a visit to Olomouc and Brno in Moravia.  The symphony is in four movements.  Its first performance was probably at a private concert.  The symphony was reworked to become the overture to Mozart's opera, "La finta semplice", K. 51, composed and performed later that year, and the overture itself was subsequently adapted further to create a new symphony, known in the Köchel 1964 (K6) catalogue as K. 46a.  The autograph of the score is preserved in the "Staatsbibliothek Preusischer Kulturbesitz" in Berlin.

Symphony No. 6 (Tchaikovsky): The Symphony No. 6 in B minor, Op. 74, Pathétique is Pyotr Ilyich Tchaikovsky's final completed symphony, written between February and the end of August 1893.  The composer entitled the work "The Passionate Symphony", employing a Russian word, Патетическая ("Pateticheskaya"), meaning "passionate" or "emotional", that was then mistranslated into French as "pathétique", "evoking pity", yet the mistranslation survived subsequent productions in every country but Russia.  The composer led the first performance in Saint Petersburg on 16/28 October of that year, nine days before his death.  The second performance, conducted by Eduard Nápravník, took place 21 days later, at a memorial concert on 6/18 November.  It included some minor corrections that Tchaikovsky had made after the premiere, and was thus the first performance of the work in the exact form in which it is known today.  The first performance in Moscow was on 4/16 December, conducted by Vasily Safonov.  It was the last of Tchaikovsky's compositions premiered in his lifetime; his last composition of all, the single-movement 3rd Piano Concerto, Op. 75, which was completed in October 1893, a short time before his death, received a posthumous premiere.

Adrian Boult: Sir Adrian Cedric Boult, CH ( ; 8 April 1889 – 22 February 1983) was an English conductor.  Brought up in a prosperous mercantile family, he followed musical studies in England and at Leipzig, Germany, with early conducting work in London for the Royal Opera House and Sergei Diaghilev's ballet company.  His first prominent post was conductor of the City of Birmingham Orchestra in 1924.  When the British Broadcasting Corporation appointed him director of music in 1930, he established the BBC Symphony Orchestra and became its chief conductor.  The orchestra set standards of excellence that were rivalled in Britain only by the London Philharmonic Orchestra (LPO), founded two years later.

Supporting paragraphs: Symphony No. 7 (Bax) Adrian Boult
Answer: 1889