Teacher: 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.
Teacher: Now, understand the problem? If you are still confused, see the following example:
Passage: In 1763, Spain traded Florida to the Kingdom of Great Britain for control of Havana, Cuba, which had been captured by the British during the Seven Years' War. It was part of a large expansion of British territory following the country's victory in the Seven Years' War. Almost the entire Spanish population left, taking along most of the remaining indigenous population to Cuba. The British soon constructed the King's Road connecting St. Augustine to Georgia. The road crossed the St. Johns River at a narrow point, which the Seminole called Wacca Pilatka and the British named "Cow Ford", both names ostensibly reflecting the fact that cattle were brought across the river there.
Solution: Who owned Cuba after the Eight Years War?
Reason: This question appears to be relevant to the passage as both involves words such as 'Cuba' and 'War' which also exist in the passage. The passage mentions that "after the war, almost the entire Spanish population left, taking along most of the remaining indigenous population to Cuba". This information is not sufficient to conclude that which country owned cuba.

Now, solve this instance: 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.
Student:
What act slowed the building of churches in Britain?