Given the task definition and input, reply with output. This task is about creating an unanswerable question based on a given passage. Construct a question that looks relevant to the given context but is unanswerable. Following are a few suggestions about how to create unanswerable questions:
(i) create questions which require satisfying a constraint that is not mentioned in the passage
(ii) create questions which require information beyond what is provided in the passage in order to answer
(iii) replace an existing entity, number, date mentioned in the passage with other entity, number, date and use it in the question
(iv) create a question which is answerable from the passage and then replace one or two words by their antonyms or insert/remove negation words to make it unanswerable.

Passage: Their endowment by a prince or monarch and their role in training government officials made these Mediterranean universities similar to Islamic madrasas, although madrasas were generally smaller and individual teachers, rather than the madrasa itself, granted the license or degree. Scholars like Arnold H. Green and Hossein Nasr have argued that starting in the 10th century, some medieval Islamic madrasahs became universities. George Makdisi and others, however, argue that the European university has no parallel in the medieval Islamic world. Other scholars regard the university as uniquely European in origin and characteristics.
What did many towns establish in the Islamic world?