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: The war had removed Bermuda's primary trading partners, the American colonies, from the empire, and dealt a harsh blow to Bermuda's merchant shipping trade. This also suffered due to the deforestation of Bermuda, as well as the advent of metal ships and steam propulsion, for which it did not have raw materials. During the course of the following War of 1812, the primary market for Bermuda's salt disappeared as the Americans developed their own sources. Control of the Turks had passed to the Bahamas in 1819.

SOLUTION: What was the primary market for Bermuda following the War of 1812?

PROBLEM: Passage: The principles of imperialism are often generalizable to the policies and practices of the British Empire "during the last generation, and proceeds rather by diagnosis than by historical description". British imperialism often used the concept of Terra nullius (Latin expression which stems from Roman law meaning 'empty land'). The country of Australia serves as a case study in relation to British settlement and colonial rule of the continent in the eighteenth century, as it was premised on terra nullius, and its settlers considered it unused by its sparse Aboriginal inhabitants.

SOLUTION:  Imperialism is less often associated with which sovereignty?

PROBLEM: Passage: The prestige of British institutions in the 19th century and the growth of the British Empire saw the British model of cabinet government, headed by a prime minister, widely copied, both in other European countries and in British colonial territories as they developed self-government. In some places alternative titles such as "premier", "chief minister", "first minister of state", "president of the council" or "chancellor" were adopted, but the essentials of the office were the same.

SOLUTION:
What istitutions were prestiges in the 1900's