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.

Ex Input:
Passage: Approximately 10,000 years ago, desertification forced hunter-gatherer societies south into the Sahel regions of northern Central Africa, where some groups settled and began farming as part of the Neolithic Revolution. Initial farming of white yam progressed into millet and sorghum, and before 3000 BC the domestication of African oil palm improved the groups' nutrition and allowed for expansion of the local populations. Bananas arrived in the region and added an important source of carbohydrates to the diet; they were also used in the production of alcoholic beverages.[when?] This Agricultural Revolution, combined with a "Fish-stew Revolution", in which fishing began to take place, and the use of boats, allowed for the transportation of goods. Products were often moved in ceramic pots, which are the first known examples of artistic expression from the region's inhabitants.

Ex Output:
How long ago did farming force hunter-gatherer societies south?


Ex Input:
Passage: Both private individuals and large production companies have used YouTube to grow audiences. Independent content creators have built grassroots followings numbering in the thousands at very little cost or effort, while mass retail and radio promotion proved problematic. Concurrently, old media celebrities moved into the website at the invitation of a YouTube management that witnessed early content creators accruing substantial followings, and perceived audience sizes potentially larger than that attainable by television. While YouTube's revenue-sharing "Partner Program" made it possible to earn a substantial living as a video producer—its top five hundred partners each earning more than $100,000 annually and its ten highest-earning channels grossing from $2.5 million to $12 million—in 2012 CMU business editor characterized YouTube as "a free-to-use... promotional platform for the music labels". In 2013 Forbes' Katheryn Thayer asserted that digital-era artists' work must not only be of high quality, but must elicit reactions on the YouTube platform and social media. In 2013, videos of the 2.5% of artists categorized as "mega", "mainstream" and "mid-sized" received 90.3% of the relevant views on YouTube and Vevo. By early 2013 Billboard had announced that it was factoring YouTube streaming data into calculation of the Billboard Hot 100 and related genre charts.

Ex Output:
How did a 2012 MCU business editor characterize YouTube?


Ex Input:
Passage: In the UK, the Medicines and Healthcare Products Regulatory Agency approves drugs for use, though the evaluation is done by the European Medicines Agency, an agency of the European Union based in London. Normally an approval in the UK and other European countries comes later than one in the USA. Then it is the National Institute for Health and Care Excellence (NICE), for England and Wales, who decides if and how the National Health Service (NHS) will allow (in the sense of paying for) their use. The British National Formulary is the core guide for pharmacists and clinicians.

Ex Output:

Who is the core clinician?