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.
Input: Passage: After World War II Hudson's realized that the limited parking space at its downtown skyscraper would increasingly be a problem for its customers. The solution in 1954 was to open the Northland Center in nearby Southfield, just beyond the city limits. It was the largest suburban shopping center in the world, and quickly became the main shopping destination for northern and western Detroit, and for much of the suburbs. By 1961 the downtown skyscraper accounted for only half of Hudson's sales; it closed in 1986. The Northland Center Hudson's, rebranded Macy's in 2006 following acquisition by Federated Department Stores, was closed along with the remaining stores in the center in March 2015 due to the mall's high storefront vacancy, decaying infrastructure, and financial mismanagement.
Output:
In what year didn't Hudson's address the issue of parking within cities?