Given the task definition and input, reply with output. 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 Deep Purple founded? Passage 1:Ross married Bertha (Bee) Halley Horecker, a singer-musician and daughter of Ross's Chicago neighbors, in 1931, received a National Research Council Fellowship for 1932, and worked as a National Research Council postdoctoral fellow at California Institute of Technology with Eric Temple Bell until 1933. Ross moved back to Chicago and led the mathematics department at an experimental school started by Ph.D.s during the Great Depression, People's Junior College, where he also taught physics. Ross became an assistant professor at St. Louis University in 1935 and stayed for about 11 years. In an interview, he said he advocated for a student who became the first black woman in the South to receive a master's degree in mathematics. This exception led the university to admit black students despite the idea's widespread unpopularity. During World War II, Ross served as a research mathematician for the U.S. Navy. He befriended Hungarian mathematician Gabor Szego while in St. Louis, who recommended Ross for a 1941 Brown University summer school that prepared young scientists to assist in the war, a program Ross attended. He occasionally worked on proximity fuzes for Stromberg-Carlson's laboratory from 1941 to 1945 before accepting a position as head of University of Notre Dame's mathematics department in 1946. He set out to change the school's research climate by inviting distinguished mathematicians including Paul Erdos, whom Ross made a full professor.
Passage 2:Holocaust is a 1978 American four part television miniseries which recounts the trajectory of the Holocaust from the perspectives of the fictional Weiss family of German Jews and that of a rising member of the SS, who gradually becomes a merciless war criminal. Holocaust highlighted numerous events which occurred up to and during World War II, such as Kristallnacht, the creation of Jewish ghettos, and later, the use of gas chambers. Although the miniseries won several awards and received positive reviews, it was criticized by others, such as the Holocaust survivor Elie Wiesel, who wrote in The New York Times that it was: "Untrue, offensive, cheap: as a TV production, the film is an insult to those who perished and to those who survived."
Passage 3:Tony met Deep Purple in the early 1970s, when the last recording of Ashton, Gardner and Dyke was a collaboration with keyboardist Jon Lord on the soundtrack for a b-movie called The Last Rebel. In the meantime, Ashton had appeared on Jon Lord's first solo album Gemini Suite in 1971. In 1973, Ashton joined the group Family for their last album and tour. That same year, he and David Coverdale and Glenn Hughes were guest vocalists on Jon Lord's second album Windows. Tony became close friends with Jon Lord. In the summer of 1974, during a break in Purple's busy touring schedule, Tony Ashton and Jon Lord recorded their album First of the Big Bands. This project was launched with a gig at the London Palladium the same year and the BBC taped a special live appearance at Golders Green Hippodrome in London. The album of this show is a tour-de-force groovy, rhythm and blues, boogie piano and Hammond organ, big band fest. Tony also contributed to Roger Glover's Butterfly Ball project. In these years, Ashton and Lord found a second home in Zermatt, an alpine resort in Switzerland, sometimes to ski, but more often to offer giant and brilliant non-profit gigs in a unique complex (one hotel-two night-clubs-two restaurants and four pubs) called "Hotel Post" which was run by American-born Karl Ivarsson. Ashton managed to come to the place almost until his death, and Jon has been a regular visitor until his death even if the "(in)famous" hotel did not exist anymore.
3