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 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: Some Samoans are spiritual and religious, and have subtly adapted the dominant religion of Christianity to 'fit in' with fa'a Samoa and vice versa. As such, ancient beliefs continue to co-exist side-by-side with Christianity, particularly in regard to the traditional customs and rituals of fa'a Samoa. The Samoan culture is centred around the principle of vāfealoa'i, the relationships between people. These relationships are based on respect, or fa'aaloalo. When Christianity was introduced in Samoa, most Samoan people converted. Currently 98% of the population identify themselves as Christian.

SOLUTION: What religion is practiced by the fa'aaloalo?

PROBLEM: Passage: Not all introduced species are invasive, nor all invasive species deliberately introduced. In cases such as the zebra mussel, invasion of US waterways was unintentional. In other cases, such as mongooses in Hawaii, the introduction is deliberate but ineffective (nocturnal rats were not vulnerable to the diurnal mongoose). In other cases, such as oil palms in Indonesia and Malaysia, the introduction produces substantial economic benefits, but the benefits are accompanied by costly unintended consequences.

SOLUTION:
What animal intentionally invaded the US waterways?