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.

Let me give you an 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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The answer to this example can be: 1
Here is why: The question refers to the 704th unit and task about war which is decribed by Passage 1.

OK. solve this:
Question: How many people live in the city that the largest railway station in Serbia is located in? Passage 1:Davis sailed for San Francisco, California, around Cape Horn in 1852, and upon arriving, engaged for a brief time as a gold miner, a lumber supercargo surveyor for a coastal steamer, and a purser for the Pacific Mail Steamship Company. In addition he helped found the Mercantile Library Association of California (its oldest public library). Under his administrative tutelage interest in the library was restored with his creation of a library catalog (an act which later lead to his poor eyesight). He resigned in 1855 and relocated to San Francisco in 1860 at which time he established the highly successful Golden Gate Flouring Mills and the Sperry Flour Company. He was elected a member of the American Antiquarian Society in 1862. When the American Civil War broke out, he served in the secretive San Francisco-based Home Guard acting to secure both the loyalty of California to then Union President Abraham Lincoln and the election of Leland Stanford as governor of California (by patrolling the polls on election day). He presided over the Produce Exchange of San Francisco from 1867 to 1877 until he was elected as a Republican to the United States House of Representatives of the Forty-fifth and Forty-sixth Congresses (March 4, 1877 - March 3, 1881), where on June 8, 1878 he spoke in support of a bill to restrict Chinese immigration. He was an unsuccessful candidate for reelection in 1880 to the Forty-seventh Congress.
 Passage 2:There is archaeological evidence such as a blade implement and arrowheads to suggest habitation as early as the Mesolithic and Neolithic eras. The Bronze Age finds in the area have proved more numerous. They have included a set of ring ditches, a rapier and several spearheads. The village is also noteworthy as the site of a substantial Iron Age hillfort, alternatively known as a bertune, which would later be pronounced "Burton" in the Norman fashion (the name of the village until the early 14th-century). Excavated in 1950–1951, The discovery of Gaulish-made samian ware and a distinctive coin, along with coarse-gritted and medieval pottery, have led archaeologists to believe that the fort was occupied by Roman soldiers sometime after their invasion of Britain in 43 AD under Vespasian. Such was not uncommon in other hill forts of the Iron Age, with Maiden Castle and Hod Hill, both in the county of Dorset, later occupied by Romans as strategic military bases.
 Passage 3:Belgrade marshalling yard () or Makiš railway station (), or Makiš freight station, is a classification yard of the Belgrade railway junction and the largest railway station in Serbia. It is located in the neighbourhood of Makiš in Čukarica of Belgrade. The railroad continues to Ostružnica in one line via park A, in the other direction to Ostružnica via park B, in third direction to Resnik via junction B near Železnik and junction K of Belgrade railway junction near Petlovo Brdo, in fourth direction to Resnik via junction R in the tunnel below Vidikovac and junction A near Kneževac, in the fifth direction to Rakovica via park B and junction R, in the sixth direction to Rakovica via park A and junction T, in the seventh direction to Rakovica via park B and junction T per second line and the eight towards direction to Jajinci. Belgrade marshalling yard consists of 120 railway tracks.

Answer:
3