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.

Ex Input:
Passage: In addition to the principal cast, Alessandro Cremona was cast as Marco Sciarra, Stephanie Sigman was cast as Estrella, and Detlef Bothe was cast as a villain for scenes shot in Austria. In February 2015 over fifteen hundred extras were hired for the pre-title sequence set in Mexico, though they were duplicated in the film, giving the effect of around ten thousand extras.

Ex Output:
Alessandro who was cast as Estrella?

Ex Input:
Passage: During the 1950s and 1960s, FBI officials became increasingly concerned about the influence of civil rights leaders, whom they believed had communist ties or were unduly influenced by them. In 1956, for example, Hoover sent an open letter denouncing Dr. T.R.M. Howard, a civil rights leader, surgeon, and wealthy entrepreneur in Mississippi who had criticized FBI inaction in solving recent murders of George W. Lee, Emmett Till, and other blacks in the South. The FBI carried out controversial domestic surveillance in an operation it called the COINTELPRO, which was short for "COunter-INTELligence PROgram." It was to investigate and disrupt the activities of dissident political organizations within the United States, including both militant and non-violent organizations. Among its targets was the Southern Christian Leadership Conference, a leading civil rights organization with clergy leadership.

Ex Output:
When did FBI officials become less concerned about Civil Rights?

Ex Input:
Passage: The Tanana Valley is another notable agricultural locus, especially the Delta Junction area, about 100 miles (160 km) southeast of Fairbanks, with a sizable concentration of farms growing agronomic crops; these farms mostly lie north and east of Fort Greely. This area was largely set aside and developed under a state program spearheaded by Hammond during his second term as governor. Delta-area crops consist predominately of barley and hay. West of Fairbanks lies another concentration of small farms catering to restaurants, the hotel and tourist industry, and community-supported agriculture.

Ex Output:
Which crops aren't produced in the Delta-area?