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 did the Walk happen? Passage 1:The Annals begin with a universal history from the creation of the world until about 1040. This portion of the work is drawn largely from other, earlier annalistic works, particularly those of Saint Bede, Isidore of Seville, and from German traditions like the Annals of Quedlinburg and Weissenburg. From about the date of 1042 onwards, however, the account is Lampert's own and he carries the history from there up to the year 1077, when the Swabian duke Rudolf of Rheinfelden was crowned anti-king by the dissident princes. Lambert's Annales are among the most important sources available for the reign of King Henry IV, the Investiture Controversy, and the Saxon Rebellion in 1073–75. Among the significant events detailed in Lampert's history are the infamous Coup of Kaiserswerth in 1062, Henry's famous Walk to Canossa where he submitted (albeit temporarily) to Pope Gregory VII, and the 1075 Battle of Langensalza where Henry's forces defeated the Saxon and Thuringian rebels. Lambert ended his work with the election of anti-king Rudolf of Swabia, stating that his own account had reached an appropriate conclusion and that another writer would be able to pick up from where he left off in chronicling this new era for the German kingdom (Rudolf was mortally wounded in the Battle on the Elster against Henry's forces in 1080).
 Passage 2:He was first elected to the Knesset in 1996 as a member of the right-wing Moledet Party, advocating voluntary transfer of Palestinian population from the West Bank and the Gaza Strip (an ideology shared by Elon). In 1999, the party allied with other right-wing parties to form the National Union party. Following the assassination of Moledet leader Rehavam Ze'evi in 2001, Elon was elected to replace him as party chairman and as Tourism Minister. He consequently served two terms as Minister of Tourism, between 2001 and 2002, and again between 2003 and 2004, both in Ariel Sharon's government. During his second spell in the cabinet, Elon attempted to foil Ariel Sharon's plan to dismiss him from the cabinet for intending to vote against the disengagement plan by going into hiding, claiming if he did not receive his dismissal in person within 48 hours of the cabinet meeting, then he would still be able to vote. Ultimately, his dismissal was deemed legal, and he was not allowed to vote in the meeting. He was re-elected in 2006, but did not run in the 2009 elections due to health issues.
 Passage 3:John H. Mercer was the third child of Harriet and John W. Mercer. He was educated at private schools in Cheltenham and, later, at Gordonstoun in Scotland. During World War II he served in the British Merchant Marines (1940–46) as a radio man. After the war he went to University of Cambridge and studied geography. At that time he came under the influence of William Vaughan Lewis. After finishing his B.A. in 1949 Mercer went to Canada, where he received his PhD in geography from McGill University in 1954. He was a Research Scholar from 1954 to 1956 at the Australian National University in Canberra, where he studied land use and population in western Samoa. He returned to Canada and worked in the Canadian Hydro-graphic Office in Ottawa as a geographer in 1957 and 1958. During 1959–60, 1961–62, 1964, and 1966, the American Geographical Society employed him at its World Data Center A for Glaciology in New York. The turning point in his career as a glaciologist was in 1960, when he became a Research Associate at The Ohio State University, in the Institute of Polar Studies (renamed the Byrd Polar Research Center). He remained at The Ohio State University until his death, becoming its first Senior Research Scientist.
1