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: What is the difference between the two melanocortin receptors? Passage 1:The main party left England by sea on 20 January 1933, stopping at Gibraltar, where the Rock of Gibraltar "offered a climbing problem or two", and Aden. Time at sea was spent discussing the problem of climbing Mount Everest and the establishment of the various camps on its northern side, as well as learning the Nepali language, in which Crawford was proficient. The party alighted at Bombay, where they were assisted by C. E. Boreham, the manager of the Army and Navy Stores. Ruttledge, an India hand, took them on sightseeing tours to Agra and Fatehpur Sikri. Passing through Calcutta, where they were entertained by the Governor of Bengal, Sir John Anderson, the expedition members proceeded to Darjeeling, where Smythe, Greene and Birnie joined them, while Ruttledge went to Siliguri to rendezvous with Shebbeare and discuss transport arrangements. At Darjeeling porters were selected for the march, Ruttledge's Sherpas from his 1932 trip, Nima Dorje and Sanam Topgye, having gone to Sola Khombu to alert prospective applicants to the existence of the British expedition. Llakpar Chedi, Lewa and Nursang were selected as sirdars. In addition, Nima Tendrup, a veteran of many expeditions to Mount Everest, as well as a number of Sherpas who had been on the recent German expeditions to Kangchenjunga, were brought along. Karma Paul, who had been on the 1922 and 1924 British expeditions, was taken as interpreter. All the porters were screened at the Darjeeling hospital, 34 per cent being found to be infected with internal parasites, and then clothed in blue-and-white striped pyjamas and given numbered identity disks.
 Passage 2:AGRP has been demonstrated to be an inverse agonist of melanocortin receptors, to be specific MC3-R and MC4-R. The melanocortin receptors, MC3-R and MC4-R, are directly linked to metabolism and body weight control. These receptors are activated by the peptide hormone α-MSH (melanocyte-stimulating hormone) and antagonized by the agouti-related protein. Whereas α-MSH acts broadly on most members of the MCR family (with the exception of MC2-R), AGRP is highly specific for only MC3-R and MC4-R. This inverse agonism not only antagonizes the action of melanocortin agonists such as α-MSH but also further decreases the cAMP produced by the affected cells. The exact mechanism by which AgRP inhibits melanocortin-receptor signalling is not completely clear. It has been suggested that Agouti-related protein binds MSH receptors and acts as a competitive antagonist of ligand binding. Studies of Agouti protein in B16 melanoma cells supported this logic. The expression of AgRP in the adrenal gland is regulated by glucocorticoids. The protein blocks α-MSH-induced secretion of corticosterone.
 Passage 3:Carlito Guansing Galvez, Jr. is a retired Filipino general and the former Chief of Staff of the Armed Forces of the Philippines. He is a graduate of the Philippine Military Academy "Sandiwa" Class of 1985. He is also known for his leadership of the AFP Western Mindanao Command during the Battle of Marawi. He is a recipient of the United States Eisenhower Fellowships in 2006 and worked on the peace process with the Moro Islamic Liberation Front in 2015 as co-Chairman on the Coordinating Committee on the Cessation of Hostilities (CCCH). He also commanded the Army 104th Brigade, and the 6th Infantry Division. He,then an Army Lieutenant, along with some PMA 1985 classmates, including Rolando Joselito Bautista was also granted amnesty from Former AFP Chief and President Fidel Ramos, during the 1989 Coup.

Answer:
2