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: Until the Church Building Act of 1818, the period saw relatively few churches built in Britain, which was already well-supplied, although in the later years of the period the demand for Non-conformist and Roman Catholic places of worship greatly increased. Anglican churches that were built were designed internally to allow maximum audibility, and visibility, for preaching, so the main nave was generally wider and shorter than in medieval plans, and often there were no side-aisles. Galleries were common in new churches. Especially in country parishes, the external appearance generally retained the familiar signifiers of a Gothic church, with a tower or spire, a large west front with one or more doors, and very large windows along the nave, but all with any ornament drawn from the classical vocabulary. Where funds permitted, a classical temple portico with columns and a pediment might be used at the west front. Decoration inside was very limited, but churches filled up with monuments to the prosperous.

SOLUTION: What act slowed the building of churches in Britain?

PROBLEM: Passage: Following al-Farabi's lead, Avicenna initiated a full-fledged inquiry into the question of being, in which he distinguished between essence (Mahiat) and existence (Wujud). He argued that the fact of existence can not be inferred from or accounted for by the essence of existing things, and that form and matter by themselves cannot interact and originate the movement of the universe or the progressive actualization of existing things. Existence must, therefore, be due to an agent-cause that necessitates, imparts, gives, or adds existence to an essence. To do so, the cause must be an existing thing and coexist with its effect.

SOLUTION: Who followed Avicenna's leadand investigated the question of being?

PROBLEM: Passage: The Great Plains is the broad expanse of flat land (a plain), much of it covered in prairie, steppe and grassland, that lies west of the Mississippi River tallgrass prairie states and east of the Rocky Mountains in the United States and Canada. This area covers parts, but not all, of the states of Colorado, Kansas, Montana, Nebraska, New Mexico, North Dakota, Oklahoma, South Dakota, Texas, and Wyoming, and the Canadian provinces of Alberta, Manitoba and Saskatchewan. The region is known for supporting extensive cattle ranching and dry farming.

SOLUTION:
What lies east of the Mississippi River tallgrass prairie states?