Question: Viennese trichord is named for which group of composers comprising Schoenberg and his pupils?
Context: In C is a musical piece composed by Terry Riley in 1964 for an indefinite number of performers.  He suggests "a group of about 35 is desired if possible but smaller or larger groups will work".  A series of short melodic fragments, "In C" is a response to the abstract academic serialist techniques devised by Schoenberg that dominated Western university composers for many decades and is often cited as the first minimalist composition (though La Monte Young's drone compositions preceded it by several years, "In C" had a greater impact on public consciousness). Walter Levin (December 6, 1924 – August 4, 2017) was the founder, first violinist, and guiding spirit of the LaSalle Quartet (active 1947–1987), which was known for its championing of contemporary composers, for its recordings of the Second Viennese School (Arnold Schoenberg, Alban Berg, and Anton Webern), as well as for its intellectually penetrating interpretations of the classical and romantic quartet repertory, in particular the late quartets of Beethoven.  Levin was also an important pedagogue, having taught many of the world’s leading string quartets, among them the Alban Berg Quartet and the Arditti Quartet; other prominent students include the conductor James Levine, the violinist Christian Tetzlaff and the pianist Stefan Litwin. Brookvale High School, opened 1975, is a mixed middle school in the village of Groby in Leicestershire, England, providing education for students aged 11–14.  It shares a large campus with Groby Community College which takes pupils from 14-19.  Its main intake comes from partner schools in Groby and the nearby villages of Ratby, Kirby Muxloe and Newtown Linford though it accepts other pupils subject to availability of places.  Its name is derived from a small group of cottages, named Brooke Vale Cottages, that formerly occupied the site where the school now stands.  The school specialises in languages and teaches French, Spanish and German to its pupils. The Sir-Karl-Popper-Schule is an integral part of a public school named Wiedner Gymanasium located in the 4th district of Vienna.  It is a special branch with experimental status for highly gifted pupils comprising grades 9 to 12.  There are two classes per year with 24 pupils in each.  Admittance is mainly based on the results of internationally acknowledged test methods conducted by an external institution. In music theory, a Viennese trichord (also Viennese fourth chord and tritone-fourth chord), named for the Second Viennese School, is prime form <0,1,6>.  It has Forte # 3-5. Twelve-tone technique—also known as dodecaphony, twelve-tone serialism, and (in British usage) twelve-note composition—is a method of musical composition devised by Austrian composer Arnold Schoenberg (1874–1951) and associated with the "Second Viennese School" composers, who were the primary users of the technique in the first decades of its existence.  The technique is a means of ensuring that all 12 notes of the chromatic scale are sounded as often as one another in a piece of music while preventing the emphasis of any one note through the use of tone rows, orderings of the 12 pitch classes.  All 12 notes are thus given more or less equal importance, and the music avoids being in a key.  Over time, the technique increased greatly in popularity and eventually became widely influential on 20th century composers.  Many important composers who had originally not subscribed to or even actively opposed the technique, such as Aaron Copland and Igor Stravinsky, eventually adopted it in their music. The Arnold Schoenberg Choir (German: "Arnold Schoenberg Chor" ) is a Viennese/Austrian choir which was founded 1972 by Erwin Ortner, who is still its artistic director.  The choir has a high reputation both among conductors and among critics and the musical scene in general.  All members of the choir have broad experience and expertise in vocal music; most of them have graduated from or are currently studying at the Vienna University of Music and Performing Arts.  The choir is named after Viennese composer Arnold Schoenberg. The Second Viennese School (German: Zweite Wiener Schule, Neue Wiener Schule ) is the group of composers that comprised Arnold Schoenberg and his pupils and close associates in early 20th century Vienna, where he lived and taught, sporadically, between 1903 and 1925.  Their music was initially characterized by late-Romantic expanded tonality and later, following Schoenberg's own evolution, a totally chromatic expressionism without firm tonal centre, often referred to as atonality; and later still, Schoenberg's serial twelve-tone technique.  Though this common development took place, it neither followed a common time-line nor a cooperative path.  Likewise, it was not a direct result of Schoenberg's teaching—which, as his various published textbooks demonstrate, was highly traditional and conservative.  Schoenberg's textbooks also reveal that the Second Viennese School spawned not from the development of his serial method, but rather from the influence of his creative example. Pyotr Ilyich Tchaikovsky's relations with the group of composers known as the Belyayev circle, which lasted from 1887 until Tchaikovsky's death in 1893, influenced all of their music and briefly helped shape the next generation of Russian composers.  This group was named after timber merchant Mitrofan Belyayev, an amateur musician who became an influential music patron and publisher after he had taken an interest in Alexander Glazunov's work.  By 1887, Tchaikovsky was firmly established as one of the leading composers in Russia.  A favorite of Tsar Alexander III, he was widely regarded as a national treasure.  He was in demand as a guest conductor in Russia and Western Europe, and in 1890 visited the United States in the same capacity.  By contrast, the fortunes of the nationalistic group of composers known as The Five, which preceded the Belyayev circle, had waned, and the group had long since dispersed; of its members, only Nikolai Rimsky-Korsakov remained fully active as a composer.  Now a professor of musical composition and orchestration at the Saint Petersburg Conservatory, Rimsky-Korsakov had become a firm believer in the Western-based compositional training that had been once frowned upon by the group. The Atlanta School of Composers is a group of contemporary classical music composers championed by Atlanta Symphony Orchestra and conductor Robert Spano through performances, recordings, and commissions.  Members of the group include Jennifer Higdon, Christopher Theofanidis, Osvaldo Golijov, and Michael Gandolfi, with Adam Schoenberg added in June 2010.  Works from the group including the following:
Answer: Second Viennese School