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: The control of associated biodiversity is one of the great agricultural challenges that farmers face. On monoculture farms, the approach is generally to eradicate associated diversity using a suite of biologically destructive pesticides, mechanized tools and transgenic engineering techniques, then to rotate crops. Although some polyculture farmers use the same techniques, they also employ integrated pest management strategies as well as strategies that are more labor-intensive, but generally less dependent on capital, biotechnology and energy.
[A]: What is one of the great polyculture challenges that farmers face?


[Q]: Passage: By the mid 18th century, the movement broadened to incorporate a greater range of Classical influences, including those from Ancient Greece. The shift to neoclassical architecture is conventionally dated to the 1750s. It first gained influence in England and France; in England, Sir William Hamilton's excavations at Pompeii and other sites, the influence of the Grand Tour and the work of William Chambers and Robert Adam, was pivotal in this regard. In France, the movement was propelled by a generation of French art students trained in Rome, and was influenced by the writings of Johann Joachim Winckelmann. The style was also adopted by progressive circles in other countries such as Sweden and Russia.
[A]: What did movement incorporate by the mid-1800s?


[Q]: Passage: Current manager, Roberto Martínez, is the fourteenth permanent holder of the position since it was established in 1939. There have also been four caretaker managers, and before 1939 the team was selected by either the club secretary or by committee. The club's longest-serving manager has been Harry Catterick, who was in charge of the team from 1961–73, taking in 594 first team matches. The Everton manager to win most domestic and international trophies is Howard Kendall, who won two Division One championships, the 1984 FA Cup, the 1984 UEFA Cup Winners' Cup, and three Charity Shields.
[A]:
In what year did Roberto Martinez become the current manager of Everton?