Definition: In this task, you're given a question, along with a context passage. The passage will not have a direct answer to the question, but can include some information and a clue for the answer. Assuming you can only obtain information about one entity in the passage, your job is to determine whether information from the passage can be used to answer the question. Indicate your choice as `a` for Yes or `b` for No.
Input: Question: What major river runs through the city where Al-Maqrizi was born? Passage: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:


b