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.

[Q]: Passage: In 1661 another Jesuit, Johann Grueber, crossed Tibet from Sining to Lhasa (where he spent a month), before heading on to Nepal. He was followed by others who actually built a church in Lhasa. These included the Jesuit Father Ippolito Desideri, 17161721, who gained a deep knowledge of Tibetan culture, language and Buddhism, and various Capuchins in 17071711, 17161733 and 17411745, Christianity was used by some Tibetan monarchs and their courts and the Karmapa sect lamas to counterbalance the influence of the Gelugpa sect in the 17th century until in 1745 when all the missionaries were expelled at the lama's insistence.
[A]: Who crossed Nepal before heading to Tibet in 1661?

[Q]: 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.
[A]: What percentage of tourists arrive in Namibia at Hosea Kutako International Airport?

[Q]: Passage: In 1976 John Goldsmith introduced autosegmental phonology. Phonological phenomena are no longer seen as operating on one linear sequence of segments, called phonemes or feature combinations, but rather as involving some parallel sequences of features which reside on multiple tiers. Autosegmental phonology later evolved into feature geometry, which became the standard theory of representation for theories of the organization of phonology as different as lexical phonology and optimality theory.
[A]:
Who founded operating tiers?