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.

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, 1716–1721, who gained a deep knowledge of Tibetan culture, language and Buddhism, and various Capuchins in 1707–1711, 1716–1733 and 1741–1745, 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.
Who crossed Nepal before heading to Tibet in 1661?

Passage: Conventional bleaching of wood pulp using elemental chlorine produces and releases into the environment large amounts of chlorinated organic compounds, including chlorinated dioxins. Dioxins are recognized as a persistent environmental pollutant, regulated internationally by the Stockholm Convention on Persistent Organic Pollutants. Dioxins are highly toxic, and health effects on humans include reproductive, developmental, immune and hormonal problems. They are known to be carcinogenic. Over 90% of human exposure is through food, primarily meat, dairy, fish and shellfish, as dioxins accumulate in the food chain in the fatty tissue of animals.
What does bleaching of meat release into the environment?

Passage: A Freedom of Information request in 2005 revealed that Eton had received £2,652 in farming subsidies in 2004 under the Common Agricultural Policy. Asked to explain under what grounds it was eligible to receive farming subsidies, Eton admitted that it was 'a bit of a mystery'. The TaxPayers' Alliance also stated that Eton had received a total of £5,300 in CAP subsidies between 2002 and 2007. Panorama revealed in March 2012 that farming subsidies were granted to Eton for 'environmental improvements', in effect 'being paid without having to do any farming at all'.

In what year was the Taxpayers' Alliance established?