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: Unlike the Baroque style that it replaced, which was mostly used for palaces and churches, and had little representation in the British colonies, simpler Georgian styles were widely used by the upper and middle classes. Perhaps the best remaining house is the pristine Hammond-Harwood House (1774) in Annapolis, Maryland, designed by the colonial architect William Buckland and modelled on the Villa Pisani at Montagnana, Italy as depicted in Andrea Palladio's I quattro libri dell'architettura ("Four Books of Architecture").

SOLUTION: What style was widely represented in British colonies?

PROBLEM: Passage: The provision of the law in Section 4 that establishes critical habitat is a regulatory link between habitat protection and recovery goals, requiring the identification and protection of all lands, water and air necessary to recover endangered species. To determine what exactly is critical habitat, the needs of open space for individual and population growth, food, water, light or other nutritional requirements, breeding sites, seed germination and dispersal needs, and lack of disturbances are considered.

SOLUTION:
What section establishes recovery goals?