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: Contrary to the diffusionist theory, it appears that there was simultaneously a structural evolution towards the pointed arch, for the purpose of vaulting spaces of irregular plan, or to bring transverse vaults to the same height as diagonal vaults. This latter occurs at Durham Cathedral in the nave aisles in 1093. Pointed arches also occur extensively in Romanesque decorative blind arcading, where semi-circular arches overlap each other in a simple decorative pattern, and the points are accidental to the design.

A: Which cathedral is the twisted arch used to match the heights of transverse and diagonal vaults?
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Q: Passage: Between 1346 and 1354, Tai Situ Changchub Gyaltsen toppled the Sakya and founded the Phagmodrupa Dynasty. The following 80 years saw the founding of the Gelug school (also known as Yellow Hats) by the disciples of Je Tsongkhapa, and the founding of the important Ganden, Drepung and Sera monasteries near Lhasa. However, internal strife within the dynasty and the strong localism of the various fiefs and political-religious factions led to a long series of internal conflicts. The minister family Rinpungpa, based in Tsang (West Central Tibet), dominated politics after 1435. In 1565 they were overthrown by the Tsangpa Dynasty of Shigatse which expanded its power in different directions of Tibet in the following decades and favoured the Karma Kagyu sect.

A: Who topped the Sakya between 1436 and 1534?
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Q: Passage: France started the Franco-Prussian War (1870–71), and was defeated by the Kingdom of Prussia and other German states. The end of the war led to the unification of Germany. Otto von Bismarck annexed Alsace and northern Lorraine to the new German Empire in 1871; unlike other members states of the German federation, which had governments of their own, the new Imperial territory of Alsace-Lorraine was under the sole authority of the Kaiser, administered directly by the imperial government in Berlin. Between 100,000 and 130,000 Alsatians (of a total population of about a million and a half) chose to remain French citizens and leave Reichsland Elsaß-Lothringen, many of them resettling in French Algeria as Pieds-Noirs. Only in 1911 was Alsace-Lorraine granted some measure of autonomy, which was manifested also in a flag and an anthem (Elsässisches Fahnenlied). In 1913, however, the Saverne Affair (French: Incident de Saverne) showed the limits of this new tolerance of the Alsatian identity.

A:
What war did Prussia start in 1870?
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