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 major river runs through the city where Al-Maqrizi was born? Passage 1:Al-Maqrīzī was born in Fatimid Cairo and spent most of his life in Egypt, When he presents himself in his books he usually stops at the 10th forefather although he confessed to some of his close friends that he can trace his ancestry to Al-Mu‘izz li-Dīn Allāh -first Fatimid caliph in Egypt and the founder of al-Qahirah- and even to Ali ibn Abi Talib. He was trained in the Hanafite school of law. Later, he switched to the Shafi'ite school and finally to the Zahirite school. Maqrizi studied theology under one of the primary masterminds behind the Zahiri Revolt, and his vocal support and sympathy with that revolt against the Mamluks likely cost him higher administrative and clerical positions with the Mamluk regime. The name Maqrizi was an attribution to a quarter of the city of Baalbek, from where his paternal grandparents hailed. Maqrizi confessed to his contemporaries that he believed that he was related to the Fatimids through the son of al-Muizz. Ibn Hajar preserves the most memorable account: his father, as they entered the al-Hakim Mosque one day, told him "My son, you are entering the mosque of your ancestor." However, his father also instructed al-Maqrizi not to reveal this information to anyone he could not trust; Walker concludes:
 Passage 2:The concept of the morphogen has a long history in developmental biology, dating back to the work of the pioneering Drosophila (fruit fly) geneticist, Thomas Hunt Morgan, in the early 20th century. Lewis Wolpert refined the morphogen concept in the 1960s with the French flag model, which described how a morphogen could subdivide a tissue into domains of different target gene expression (corresponding to the colours of the French flag). This model was championed by the leading Drosophila biologist, Peter Lawrence. Christiane Nusslein-Volhard was the first to identify a morphogen, Bicoid, one of the transcription factors present in a gradient in the Drosophila syncitial embryo. She was awarded the 1995 Nobel Prize in Physiology and Medicine for her work explaining the morphogenic embryology of the common fruit fly. Groups led by Gary Struhl and Stephen Cohen then demonstrated that a secreted signalling protein, Decapentaplegic (the Drosophila homologue of transforming growth factor beta), acted as a morphogen during the later stages of Drosophila development.
 Passage 3:Sefer ha-Mizrachi is a supercommentary on Rashi's commentary on the Torah. It is counted in its own right as among the most important commentaries on the Torah. It was first published in Venice in 1527 after Mizrachi's death, by his son Israel. Mizrachi himself considered his commentary on Rashi the most important of his works (Responsa, Nos. 5, 78). The work shows Rashi's Talmudic and midrashic sources, and elucidates all obscure passages. It was written, partially, to defend Rashi from the strictures of the later commentators, particularly Nachmanides. A compendium by Jacob Marcaria was published under the title Kitzur Mizrachi (Trento, 1561), and later, one by Isaac ha-Kohen of Ostroh, entitled Mattenat 'Ani (Prague, 1604-9). Several commentaries have been written on Mizrachi, including Yeri'ot Shlomo by Solomon Luria (Maharshal), a supercommentary on Sefer ha-Mizrachi by Barzillai ben Baruch Jabez, and strictures on the work by Samuel Edels, (Maharsha).
1