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.

Example Input: Passage: To be considered 'enriched', the uranium-235 fraction should be between 3% and 5%. This process produces huge quantities of uranium that is depleted of uranium-235 and with a correspondingly increased fraction of uranium-238, called depleted uranium or 'DU'. To be considered 'depleted', the uranium-235 isotope concentration should be no more than 0.3%. The price of uranium has risen since 2001, so enrichment tailings containing more than 0.35% uranium-235 are being considered for re-enrichment, driving the price of depleted uranium hexafluoride above $130 per kilogram in July 2007 from $5 in 2001.
Example Output: Between what percent fraction range of uranium-235 is uranium regarded as unenriched?

Example Input: Passage: Acute myocardial infarction refers to two subtypes of acute coronary syndrome, namely non-ST-elevated and ST-elevated MIs, which are most frequently (but not always) a manifestation of coronary artery disease. The most common triggering event is the disruption of an atherosclerotic plaque in an epicardial coronary artery, which leads to a clotting cascade, sometimes resulting in total occlusion of the artery. Atherosclerosis is the gradual buildup of cholesterol and fibrous tissue in plaques in the wall of arteries (in this case, the coronary arteries), typically over decades. Bloodstream column irregularities visible on angiography reflect artery lumen narrowing as a result of decades of advancing atherosclerosis. Plaques can become unstable, rupture, and additionally promote the formation of a blood clot that occludes the artery; this can occur in minutes. When a severe enough plaque rupture occurs in the coronary arteries, it leads to MI (necrosis of downstream myocardium). It is estimated that one billion cardiac cells are lost in a typical MI.
Example Output: How many subtypes does ST-elevated MI have?

Example Input: Passage: The classification of speech varieties as dialects or languages and their relationship to other varieties of speech can be controversial and the verdicts inconsistent. English and Serbo-Croatian illustrate the point. English and Serbo-Croatian each have two major variants (British and American English, and Serbian and Croatian, respectively), along with numerous other varieties. For political reasons, analyzing these varieties as "languages" or "dialects" yields inconsistent results: British and American English, spoken by close political and military allies, are almost universally regarded as dialects of a single language, whereas the standard languages of Serbia and Croatia, which differ from each other to a similar extent as the dialects of English, are being treated by some linguists from the region as distinct languages, largely because the two countries oscillate from being brotherly to being bitter enemies. (The Serbo-Croatian language article deals with this topic much more fully.)
Example Output:
What is can be controversial with consistent verdicts?