Question: Which opera, Iphigénie en Aulide or Lulu,  is an opera in three acts by Alban Berg"?
Context: Styled a "festa teatrale", "Le feste d'Apollo" consists of a prologue and three self-contained acts on the model of French "opéra-ballet" (the court of Parma was passionately interested in French culture).  Gluck knew the Archduchess Maria Amalia well as she had sung in two of his operas, "Il Parnaso confuso" and "La corona", in Vienna.  The composer recycled a lot of music from his earlier operas in the score of "Le feste".  In fact, the whole of the third act, "Orfeo", is a shorter reworking of his most famous piece, "Orfeo ed Euridice" (1762).  The overture to the prologue is taken from "Telemaco".  Gluck later reused some of the choruses in two of the operas he wrote for Paris, "Iphigénie en Aulide" and "Iphigénie en Tauride". Earth Spirit (1895) ("Erdgeist") is a play by the German dramatist Frank Wedekind.  It forms the first part of his pairing of 'Lulu' plays; the second is "Pandora's Box" (1904), both depicting a society "riven by the demands of lust and greed".  In German folklore an "erdgeist" is a gnome, first described in Goethe's "Faust" (1808).  Together with "Pandora's Box", Wedekind's play formed the basis for the silent film "Pandora's Box" (1929) starring Louise Brooks and the opera "Lulu" by Alban Berg (1935, premiered posthumously in 1937). Magdaléna Hajóssyová (born 25 July 1946, Bratislava) is a classical Slovak soprano who has had an active international career singing in operas, concerts, and recitals since the late 1960s.  She has been particularly active at the Prague State Opera where she has been a principal artist since 1972.  She has also had a long and fruitful partnership with the Berlin State Opera beginning in 1975.  In 1977, 1981, and 1987, she won the Berlin Critic's Prize for her portrayal of the roles of Margarete in Charles Gounod's "Faust", the Elektra in Mozart's "Idomeneo", Carl Maria von Weber's "Euryanthe", and Christoph Willibald Gluck's "Iphigénie en Aulide". François-Louis Gand Le Bland Du Roullet (10 April 1716 in Normanville – 2 August 1786 in Paris) was a French diplomat and playwright.  He is chiefly remembered today as the librettist of Gluck's operas "Iphigénie en Aulide" and "Alceste" (1776 French version).  He also co-wrote (with Louis-Théodore de Tschudi) the libretto for Salieri's opera "Les Danaïdes". Lulu (composed from 1929–1935, premièred incomplete in 1937 and complete in 1979) is an opera in three acts by Alban Berg.  The German-language libretto was adapted by Berg himself from Frank Wedekind's two "Lulu" plays, "Erdgeist" ("Earth Spirit", 1895) and "Die Büchse der Pandora" ("Pandora's Box", 1904).  Berg died before completing the third and final act, and in the following decades, the opera was typically performed incomplete.  Since its publication in 1979, however, the Friedrich Cerha orchestration has become popular.  Theodor W. Adorno wrote "The opera "Lulu" is one of those works that reveals the extent of its quality the longer and more deeply one immerses oneself in it." The Mecklenburg State Theatre (German: "Mecklenburgisches Staatstheater Schwerin" ) is the principal theatre of Schwerin in Germany.  Its main theatre (or "Grosses Haus") seats 650 people and is used for the performance of plays, opera, musical theatre and ballet.  Designed by Georg Daniel, it was built between 1883 and 1886 after the previous theatre had been destroyed by fire in 1882.  The theatre was inaugurated on 3 October 1886 with a performance of Gluck's "Iphigénie en Aulide" with Marie Wittich in the title role.  The complex also includes the State Museum in Schwerin ("Staatliche Museum Schwerin") and a 240-seat concert hall, now used for performances of chamber works.  All theatres were closed for the Autumn season of 1944, with the staff drafted wherever possible.  By German WW2 standards wartime casualties and destruction by bombing in Schwerin were small, in spite of nightly RAF raids and the droning of massive bomber pulks as silver specks on the sky during the day on their way to Berlin.  Americans were the first to enter the town in the spring of 1945, handing it over to the British until the Russians arrived.  These ordered the immediate reopening of the theatre, taking great interest in light operas and operettas as an art they very much appreciated, but until then out of their reach in most parts of Stalin's Soviet Union.  Not familiar with Central European culture, one saw their well-fed ladies wearing night gowns during the invariably full houses as a substitute for an evening dress.  In the immediate years to follow, there was a gradual exodus of key staff to the West, where few found equivalent employment.  The ensuing vacancies provided new chances for many musicians, who were prepared to stay in East Germany to gain important positions there in their later career. Iphigénie en Tauride (English: "Iphigeneia in Tauris") is an opera by the French composers Henri Desmarets and André Campra.  It takes the form of a "tragédie en musique" in a prologue and five acts.  The libretto is by Joseph-François Duché de Vancy with additions by Antoine Danchet.  Desmarets had begun work on the opera around 1696 but abandoned it when he was forced to go into exile in 1699.  Campra and his regular librettist Danchet took up the piece and wrote the prologue, most of Act Five, two arias in Act One, an aria for Acts Two and Three, and two arias for the fourth act.  The plot is ultimately based on Euripides' tragedy "Iphigeneia in Tauris". Iphigénie en Aulide ("Iphigeneia in Aulis") is an opera in three acts by Christoph Willibald Gluck, the first work he wrote for the Paris stage.  The libretto was written by François-Louis Gand Le Bland Du Roullet and was based on Jean Racine's tragedy "Iphigénie".  It was premiered on 19 April 1774 by the Paris Opéra in the second Salle du Palais-Royal and revived in a slightly revised version the following year. Wozzeck (] ) is the first opera by the Austrian composer Alban Berg.  It was composed between 1914 and 1922 and first performed in 1925.  The opera is based on the drama "Woyzeck", which was left incomplete by the German playwright Georg Büchner at his death.  Berg attended the first production in Vienna of Büchner's play on 5 May 1914, and knew at once that he wanted to base an opera on it.  From the fragments of unordered scenes left by Büchner, Berg selected fifteen to form a compact structure of three acts with five scenes each.  He adapted the libretto himself, retaining "the essential character of the play, with its many short scenes, its abrupt and sometimes brutal language, and its stark, if haunted, realism..." Robin Guarino (born April 3, 1960) is an opera and film director.  She has directed operas such as "The Marriage of Figaro", "Don Giovanni", "Lohengrin", "Così fan tutte" , and "The Magic Flute" at the Metropolitan Opera.  Also, she has directed at Seattle Opera, Glimmerglass Opera, Chautauqua Opera, Virginia Opera, and Wolf Trap Opera.  She continues to direct, most recently "L'etoile" and "The Marriage of Figaro" for the Wolf Trap Opera Festival, " La Calisto", "The Magic Flute" and "Iphigénie en Aulide" for Juilliard Opera Center, and at Gotham Chamber Opera, "Il Signor Bruschino".  She currently holds the J. Ralph Corbett Distinguished Chair in Opera at the University of Cincinnati College-Conservatory of Music."
Answer: Lulu