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: The first extant Estonian book is a bilingual German-Estonian translation of the Lutheran catechism by S. Wanradt and J. Koell dating to 1535, during the Protestant Reformation period. An Estonian grammar book to be used by priests was printed in German in 1637. The New Testament was translated into southern Estonian in 1686 (northern Estonian, 1715). The two languages were united based on northern Estonian by Anton thor Helle.

SOLUTION: Who wrote the last Estonian book? 

PROBLEM: Passage: The island experienced large-scale immigration over the 20th century, especially after the Second World War. Bermuda has a diverse population including both those with relatively deep roots in Bermuda extending back for centuries, and newer communities whose ancestry results from recent immigration, especially from Britain, North America, the West Indies, and the Portuguese Atlantic islands (especially the Azores), although these groups are steadily merging. About 46% of the population identified themselves with Bermudian ancestry in 2010, which was a decrease from the 51% who did so in the 2000 census. Those identifying with British ancestry dropped by 1% to 11% (although those born in Britain remain the largest non-native group at 3,942 persons). The number of people born in Canada declined by 13%. Those who reported West Indian ancestry were 13%. The number of people born in the West Indies actually increased by 538. A significant segment of the population is of Portuguese ancestry (10%), the result of immigration over the past 160 years, of whom 79% have residency status.

SOLUTION: During what century was the diverse immigration?

PROBLEM: Passage: In 1877, the Protestant James Cameron from the China Inland Mission walked from Chongqing to Batang in Garzê Tibetan Autonomous Prefecture, Sichuan province, and "brought the Gospel to the Tibetan people." Beginning in the 20th century, in Diqing Tibetan Autonomous Prefecture in Yunnan, a large number of Lisu people and some Yi and Nu people converted to Christianity. Famous earlier missionaries include James O. Fraser, Alfred James Broomhall and Isobel Kuhn of the China Inland Mission, among others who were active in this area.

SOLUTION:
Where did Cameron James walk in 1877?