In this task, you're given a question, along with three passages, 1, 2, and 3. Your job is to determine which passage can be used to answer the question by searching for further information using terms from the passage. Indicate your choice as 1, 2, or 3.
Example: Question: When did the operation during which the 704th dropped supplies to allied troops near Nijmegen begin? Passage 1: The group was occasionally diverted from strategic missions to carry out air support and interdiction missions. It supported Operation Overlord, the invasion of Normandy by attacking transportation targets, including bridges, along with airfields and strong points in France. On D Day, the squadron and the rest of the 446th Group led the first heavy bomber mission of the day. The 446th aided ground forces at Caen and Saint-Lô during July by hitting bridges, gun batteries, and enemy troops. During Operation Market Garden, the attempt to seize a bridgehead across the Rhine in the Netherlands, the 704th dropped supplies to allied troops near Nijmegen. It struck lines of communications during the Battle of the Bulge. During Operation Varsity in March 1945, it supplied ground and airborne troops near Wesel. The squadron flew its last combat mission on 25 April 1945 against Salzburg, Austria. The group had flown 273 missions and had lost 58 aircraft during the war,
. Passage 2: John Ford (1894–1973) was an American film director whose career spanned from 1913 to 1971. During this time he directed more than 140 films. Born in Maine, Ford entered the filmmaking industry shortly after graduating from high school with the help of his older brother, Francis Ford, who had established himself as a leading man and director for Universal Studios. After working as an actor, assistant director, stuntman, and prop man – often for his brother – Universal gave Ford the opportunity to direct in 1917. Initially working in short films, he quickly moved into features, largely with Harry Carey as his star. In 1920 Ford left Universal and began working for the Fox Film Corporation. During the next ten years he directed more than 30 films, including the westerns The Iron Horse (1924) and 3 Bad Men (1926), both starring George O'Brien, the war drama Four Sons and the Irish romantic drama Hangman's House (both 1928 and both starring Victor McLaglen). In the same year of these last two films, Ford directed his first all-talking film, the short Napoleon's Barber. The following year he directed his first all-talking feature, The Black Watch.
. Passage 3: Since the late 1970s, the central part of NYU is its Washington Square campus in the heart of Greenwich Village. Despite being public property, and expanding the Fifth Avenue axis into Washington Square Park, the Washington Square Arch is the unofficial symbol of NYU. Until 2008, NYU's commencement ceremony was held in Washington Square Park. However, due to space constraints, ceremonies are now held at the Yankee Stadium. Important facilities at Washington Square are the Elmer Holmes Bobst Library, designed by Philip Johnson and Richard Foster, who also designed several other structures, such as Tisch Hall, Meyer Hall, and the Hagop Kevorkian Center. When designing these buildings Johnson and Foster also set up a master plan for a complete redesign of the NYU Washington Square campus. However, it was never implemented. Other historic buildings include the Silver Center (formerly known as "Main building"); the Brown Building of Science; Judson Hall, which houses the King Juan Carlos I of Spain Center; Vanderbilt Hall, the historic townhouse row on Washington Square North; The Grey Art Gallery at 100 Washington Square East, housing the New York University art collection and featuring museum quality exhibitions; the Kaufman Management Center; and the Torch Club – the NYU dining and club facility for alumni, faculty, and administrators. Just a block south of Washington Square is NYU's Washington Square Village, housing graduate students and junior and senior faculty residences in the Silver Towers, designed by I. M. Pei, where an enlargement of Picasso's sculpture Bust of Sylvette (1934) is displayed.
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Example solution: 1
Example explanation: The question refers to the 704th unit and task about war which is decribed by Passage 1.

Problem: Question: How many areas of study did Boston University offer degrees in the year Mairson began working there as a Visiting Professor? Passage 1:Flags is a 1985 album by the duo Moraz-Bruford. Unlike their prior effort Music for Piano and Drums, which featured only an acoustic drum kit and grand piano, this recording expanded their musical palette by including a Kurzweil 250 synthesizer and electronic percussion. Keyboardist Patrick Moraz and drummer Bill Bruford had both previously been members of the progressive rock band Yes (though at different points in time) and also appeared together on Chris Squire's first solo album Fish Out of Water. During the recording of this album, Moraz was a member of The Moody Blues, while Bruford's band King Crimson had just begun a hiatus that would last for ten years. Flags features ten instrumental works, including a drum solo based on Max Roach's "The Drum Also Waltzes".
 Passage 2:Mairson received a B.A. in Mathematics from Yale University in 1978 and a Ph.D. in Computer Science from Stanford University in 1984 under the supervision of Jeffrey Ullman. His Ph.D. thesis, The Program Complexity of Searching a Table, won the Machtey Award at the 1983 IEEE Symposium on Foundations of Computer Science (FOCS). Mairson was a Postdoctoral researcher at INRIA Rocqencourt from 1984 to 1985, at Stanford University in 1985, and at the University of Oxford in 1986. He held a Visiting Professor position from 1999 to 2001 at Boston University. From 2005 to 2007, Mairson has served as the Chair of the Faculty Senate at Brandeis. He is currently an Associate Editor of the journal Logical Methods in Computer Science and Information and Computation, and sits on the editorial board of Higher-Order and Symbolic Computation.
 Passage 3:Pyotr Filippovich Berestov (; , Berestovo – November 26, 1961, Zaporozhye) was a Red Army major general during the Second World War. Drafted into the Imperial Russian Army in 1917, Berestov participated in the Russian Revolution. He was drafted into the Red Army, fighting in the Russian Civil War and the Polish–Soviet War. He became a Red Army officer and served in several positions during the interwar period. Berestov was arrested and released during the Great Purge. He fought in the Winter War as a regimental commander. In the early days after the German invasion of the Soviet Union, he was given command of a People's Militia regiment, which was converted into a regular regiment. Berestov led the regiment in the early period of the Battle of Moscow and transferred to lead a regiment of the 82nd Motor Rifle Division. Berestov became the division's commander and in the spring of 1942 briefly led the 50th Rifle Division. In April, he took command of the 331st Rifle Division, which he led during the rest of the war. For his leadership, Berestov was awarded the title Hero of the Soviet Union in late June 1945. Postwar he commanded the 72nd Guards Rifle Division, which was downsized into a brigade, and the 43rd Guards Rifle Brigade, which became the 113th Guards Rifle Division. Berestov retired in 1955 and lived in Zaporizhia until his death in 1961.
Solution: 2