You will be given a definition of a task first, then an example. Follow the example to solve a new instance of the task.
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.

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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Solution: 1
Why? The question refers to the 704th unit and task about war which is decribed by Passage 1.

New input: Question: How many students are enrolled at the school where Thomas taught? Passage 1:A July 25, 2019 telephone call between Trump and Ukraine president Volodymyr Zelensky led in September to a whistleblower complaint and an impeachment inquiry against Trump. Two weeks after the inquiry was launched, Trump claimed in a conference call with Congressional Republican leaders that he had only made the telephone call at Perry's urging. Perry's spokesperson said that Perry had suggested Trump discuss energy security with Zelensky, but energy was not mentioned in the publicly released memo about the conversations, which instead focused on Trump asking Zelensky to launch investigations into Joe Biden, Hunter Biden, Crowdstrike, and the 2016 U.S. presidential election. Per Trump's direction earlier this year, Perry spoke with Rudy Giuliani about Ukraine, which Mick Mulvaney confirmed. Perry denied ever mentioning the Bidens in his discussions with Trump or Ukrainian officials. Mulvaney had put Gordon Sondland, Kurt Volker, and Perry in charge of managing the Ukraine–United States relations instead of diplomats at the National Security Council and the US Department of State. 
 Passage 2:Monckton-Arundell was commissioned a second lieutenant in the Nottinghamshire (Sherwood Rangers) Yeomanry on 1 January 1900, and promoted to lieutenant on 11 June 1902. In 1904, he joined the First Life Guards, the senior regiment of the British Army that makes up the Household Cavalry, where he rose to the rank of colonel. During the First World War he was appointed as adjutant general and quartermaster general. He was of the Royal Artillery (1933–35). In 1933 he was appointed Colonel Commandant of the Honourable Artillery Company (HAC) until 1935, when he relinquished it on appointment as Governor-General of New Zealand. Upon retirement from his post as governor-general he returned as Colonel Commandant of the HAC until his death. He was also appointed Honorary Colonel of the 7th (Robin Hood) Battalion, Sherwood Foresters (later 42nd (The Robin Hoods, Sherwood Foresters) Anti-Aircraft Battalion, Royal Engineers) in 1933.
 Passage 3:Thomas Christian David (December 22, 1925 – January 19, 2006) was an Austrian composer, conductor, choral conductor, and flutist. David was born in Wels, Upper Austria in 1925. He moved to Germany in 1934 at the age of nine with his father, composer Johann Nepomuk David, and mother. Thomas's younger brother, Lukas David, (born 1934) later became a violinist. In 1967, at the age of forty-two, he married (), a Persian Opera singer and they moved to Iran. David was the chief conductor of the orchestra of the National Iranian Television NITV, and also taught at the University of Tehran for seven years until 1973. He had an enormous and invaluable role in the growth and development of the Classical music in Iran. He conducted numerous masterpieces in different venues in Iran from late 1960s to late 1990s.

Solution:
3