TASK DEFINITION: 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.
PROBLEM: Passage: European colonialism in the Sahara began in the 19th century. France conquered the regency of Algiers from the Ottomans in 1830, and French rule spread south from Algeria and eastwards from Senegal into the upper Niger to include present-day Algeria, Chad, Mali then French Sudan including Timbuktu, Mauritania, Morocco (1912), Niger, and Tunisia (1881). By the beginning of the 20th century, the trans-Saharan trade had clearly declined because goods were moved through more modern and efficient means, such as airplanes, rather than across the desert.

SOLUTION: When did the Ottomans conquer France?

PROBLEM: Passage: Numerous plays are put on every year at Eton College; there is one main theatre, called the Farrer (seating 400) and 2 Studio theatres, called the Caccia Studio and Empty Space (seating 90 and 80 respectively). There are about 8 or 9 house productions each year, around 3 or 4 "independent" plays (not confined solely to one house, produced, directed and funded by Etonians) and three school plays, one specifically for boys in the first two years, and two open to all years. The School Plays have such good reputations that they are normally fully booked every night. Productions also take place in varying locations around the School, varying from the sports fields to more historic buildings such as Upper School and College Chapel.

SOLUTION: How many people can sit in College Chapel?

PROBLEM: Passage: Ibn Sīnā wrote extensively on early Islamic philosophy, especially the subjects logic, ethics, and metaphysics, including treatises named Logic and Metaphysics. Most of his works were written in Arabic – then the language of science in the Middle East – and some in Persian. Of linguistic significance even to this day are a few books that he wrote in nearly pure Persian language (particularly the Danishnamah-yi 'Ala', Philosophy for Ala' ad-Dawla'). Ibn Sīnā's commentaries on Aristotle often criticized the philosopher,[citation needed] encouraging a lively debate in the spirit of ijtihad.

SOLUTION:
Who composed most of their works in Greek?