Definition: 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.
Input: Question: What countries battled in the Battle of Kursk? Passage 1:Emperor Huizong of Song (7 June 1082 – 4 June 1135), personal name Zhao Ji, was the eighth emperor of the Song dynasty in China. He was also a very well-known calligrapher. Born as the 11th son of Emperor Shenzong, he ascended the throne in 1100 upon the death of his elder brother and predecessor, Emperor Zhezong, because Emperor Zhezong's only son died prematurely. He lived in luxury, sophistication and art in the first half of his life. In 1126, when the Jurchen-led Jin dynasty invaded the Song dynasty during the Jin–Song Wars, Emperor Huizong abdicated and passed on his throne to his eldest son, Zhao Huan who assumed the title Emperor Qinzong while Huizong assumed the honorary title of Taishang Huang (or "Retired Emperor"). The following year, the Song capital, Bianjing, was conquered by Jin forces in an event historically known as the Jingkang Incident. Emperor Huizong, along with Emperor Qinzong and the rest of their family, were taken captive by the Jurchens and brought back to the Jin capital, Huining Prefecture in 1128. The Jurchen ruler, Emperor Taizong of Jin, gave the former Emperor Huizong a title, Duke Hunde (literally "Besotted Duke"), to humiliate him. After his surviving son, Zhao Gou, declared himself as the dynasty's tenth emperor as Emperor Gaozong, the Jurchens used him, Qinzong, and other imperial family members to put pressure on Gaozong and his court to surrender. Emperor Huizong died in Wuguo after spending about nine years in captivity.
 Passage 2:The division traced its heritage back to the 7th Guards Tank Corps, formed during World War II in July 1943 from the 15th Tank Corps for its performance in Operation Kutuzov, the Soviet counteroffensive after the Battle of Kursk. It was part of the 3rd Guards Tank Army during the war, and was converted into a tank division like the rest of the tank corps in 1945. Stationed in Czechoslovakia postwar, it was briefly downsized into a regiment in 1946 and relocated to eastern Germany in 1947, becoming part of the Group of Soviet Occupation Forces in Germany, which later became the Group of Soviet Forces in Germany (GSFG). The division was stationed at Roßlau in East Germany for the rest of the Cold War and participated in the Warsaw Pact invasion of Czechoslovakia, Operation Danube, in August 1968. For much of the 1980s it formed part of the 3rd Red Banner Army. As the Cold War wound down, the troops of the GSFG, renamed the Western Group of Forces in 1989, were pulled out of Germany, and the 7th Guards Tank Division was withdrawn to Pyriatyn in Ukraine, where it became a storage base in July 1990.
 Passage 3:Cumberlidge played for Stoke City, before joining Port Vale as an amateur in October 1936. He made his debut in February 1937, and signed professional forms the following month. He made eight Third Division North appearances in the 1936–37 season, and played 23 league games in the 1937–38 season. He featured 35 times in the Third Division South in the 1938–39 campaign. He converted to left-half for the 1939–40 season, having previously been used as a left-back and inside-forward. After the conclusion of World War II, he was out of favour and barely played before he was transferred to Northwich Victoria. He managed the "Vics" in the Cheshire County League in 1968.

Output:
2