You will be given a definition of a task first, then some input 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: What year was the city founded where the German Sixth Army was encircled? Passage 1:Elem was born in Itta Bena, Mississippi, United States. He studied both Robert Nighthawk and Ike Turner playing live, which inspired his own early rhythm guitar playing. By 1948, Elem had relocated to Chicago, Illinois, where he spent the rest of his life. Shortly after arriving, Elem picked up employment backing Arthur "Big Boy" Spires and then Lester Davenport. To avoid being in a large batch of jobbing rhythm guitarists all seeking work, Elem moved over to playing the electric bass guitar. In 1956, this instrument was something of a rarity in Chicago, and Elem formed a band with the harmonica player Earl Payton, and a young Freddie King on lead guitar. The same year, King recorded his debut single for El-Bee Records. The A-side was "Country Boy", a duet with Margaret Whitfield. The B-side, "That's What You Think", was a King vocal. Both tracks featured the guitar of Robert Lockwood Jr., and the bass playing of Elem. That relative success saw King installed as the bandleader, but Elem stayed mostly with King for the next eight years. During the 1950s and 1960s, Elem regularly appeared in Chicago's burgeoning club environment, mainly on the West Side. He variously backed Magic Sam, Junior Wells, Shakey Jake Harris, Jimmy Dawkins, and Luther Allison, in addition to having a brief spell in Otis Rush's backing band.
Passage 2:As the German Sixth Army was encircled in Stalingrad, the Red Army undertook a series of wider attacks against the rest of Army Group South. These culminated on 2 January 1943 when the Red Army launched Operation Star and Operation Gallop, which between January and early February broke German defenses and led to the Soviet recapture of Kharkov, Belgorod, Kursk, as well as Voroshilovgrad and Izium. The Soviet victories caused participating Soviet units to over-extend themselves, though this was largely due to Manstein's strategy of controlled retreat towards the Dneiper. Freed on 2 February by the surrender of the German Sixth Army, the Red Army's Central Front turned its attention west and on 25 February expanded its offensive against both Army Group South and Army Group Center. Months of continuous operations had taken a heavy toll on the Soviet forces and some divisions were reduced to 1,0002,000 combat effective soldiers. On 19 February, Field Marshal Erich von Manstein launched his Kharkov counterstrike, using the fresh II SS Panzer Corps and two panzer armies. Manstein benefited greatly from the massive air support of Field Marshal Wolfram von Richthofen's Luftflotte 4, whose 1,214 aircraft flew over 1,000 sorties per day from 20 February to 15 March to support the German Army, a level of airpower equal to that during the Case Blue strategic offensive a year earlier.
Passage 3:Mainly due to Diego Milito's 23 goals in 200607 (he finished third to Roma's Francesco Totti and Real Madrid's Ruud van Nistelrooy 26 and 25 goals, respectively in the European Golden Shoe race), Real Zaragoza finished in sixth position, thus qualifying to the UEFA Cup. However, the following season ended in relegation for the second time in the decade with the side also being eliminated in the first round in European competition. Legendary club coach Victor Fernandez returned for a second spell, although he was sacked in January 2008, as the club had four managers during the campaign. On the last matchday, a brace from Ricardo Oliveira proved insufficient in a 23 away loss against Mallorca, with the team totalling 42 points to Osasuna's 43.

Output:
2