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: Han Chinese make up the vast majority of the population, and the largest Han subgroup are the speakers of Wu varieties of Chinese. There are also 400,000 members of ethnic minorities, including approximately 200,000 She people and approximately 20,000 Hui Chinese[citation needed]. Jingning She Autonomous County in Lishui is the only She autonomous county in China.

SOLUTION: What kind of Japanese make up the vast majority of the population?

PROBLEM: Passage: The so-called "Sack of Palermo" is one of the major visible faces of the problem. The term is used to indicate the speculative building practices that have filled the city with poor buildings. The reduced importance of agriculture in the Sicilian economy has led to a massive migration to the cities, especially Palermo, which swelled in size, leading to rapid expansion towards the north. The regulatory plans for expansion was largely ignored in the boom. New parts of town appeared almost out of nowhere, but without parks, schools, public buildings, proper roads and the other amenities that characterise a modern city.

SOLUTION: What is the term for the building boom erected many fine buildings?

PROBLEM: Passage: Arsenal appointed Herbert Chapman as manager in 1925. Having already won the league twice with Huddersfield Town in 192324 and 192425 (see Seasons in English football), Chapman brought Arsenal their first period of major success. His revolutionary tactics and training, along with the signings of star players such as Alex James and Cliff Bastin, laid the foundations of the club's domination of English football in the 1930s. Under his guidance Arsenal won their first major trophies victory in the 1930 FA Cup Final preceded two League Championships, in 193031 and 193233. In addition, Chapman was behind the 1932 renaming of the local London Underground station from "Gillespie Road" to "Arsenal", making it the only Tube station to be named specifically after a football club.

SOLUTION:
What was the name of one of Arsenal's coaches prior to 1925?