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: During the 1950s and 1960s, FBI officials became increasingly concerned about the influence of civil rights leaders, whom they believed had communist ties or were unduly influenced by them. In 1956, for example, Hoover sent an open letter denouncing Dr. T.R.M. Howard, a civil rights leader, surgeon, and wealthy entrepreneur in Mississippi who had criticized FBI inaction in solving recent murders of George W. Lee, Emmett Till, and other blacks in the South. The FBI carried out controversial domestic surveillance in an operation it called the COINTELPRO, which was short for "COunter-INTELligence PROgram." It was to investigate and disrupt the activities of dissident political organizations within the United States, including both militant and non-violent organizations. Among its targets was the Southern Christian Leadership Conference, a leading civil rights organization with clergy leadership.

SOLUTION: When did FBI officials become less concerned about Civil Rights?

PROBLEM: Passage: The capital city of Windhoek plays a very important role in Namibia's tourism due to its central location and close proximity to Hosea Kutako International Airport. According to The Namibia Tourism Exit Survey, which was produced by the Millennium Challenge Corporation for the Namibian Directorate of Tourism, 56% of all tourists visiting Namibia during the time period, 2012 - 2013, visited Windhoek. Many of Namibia's tourism related parastatals and governing bodies such as Namibia Wildlife Resorts, Air Namibia and the Namibia Tourism Board as well as Namibia's tourism related trade associations such as the Hospitality Association of Namibia are also all headquartered in Windhoek. There are also a number of notable hotels in Windhoek such as Windhoek Country Club Resort and some international hotel chains also operate in Windhoek, such as Avani Hotels and Resorts and Hilton Hotels and Resorts.

SOLUTION: What percentage of tourists arrive in Namibia at Hosea Kutako International Airport?

PROBLEM: Passage: In an influential 1988 paper, Timothy Rowe defined Mammalia phylogenetically as the crown group mammals, the clade consisting of the most recent common ancestor of living monotremes (echidnas and platypuses) and therian mammals (marsupials and placentals) and all descendants of that ancestor. Since this ancestor lived in the Jurassic period, Rowe's definition excludes all animals from the earlier Triassic, despite the fact that Triassic fossils in the Haramiyida have been referred to the Mammalia since the mid-19th century.

SOLUTION:
How did Timothy Rowe define Mammalia in the mid 19th century?