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.

Example Input: Passage: The southern side of Miami includes Coral Way, The Roads and Coconut Grove. Coral Way is a historic residential neighborhood built in 1922 connecting Downtown with Coral Gables, and is home to many old homes and tree-lined streets. Coconut Grove was established in 1825 and is the location of Miami's City Hall in Dinner Key, the Coconut Grove Playhouse, CocoWalk, many nightclubs, bars, restaurants and bohemian shops, and as such, is very popular with local college students. It is a historic neighborhood with narrow, winding roads, and a heavy tree canopy. Coconut Grove has many parks and gardens such as Villa Vizcaya, The Kampong, The Barnacle Historic State Park, and is the home of the Coconut Grove Convention Center and numerous historic homes and estates.
Example Output: Along with Coconut Grove and Coral Way, what is notably unpresent in southern Miami?

Example Input: Passage: The defence estate is divided as training areas & ranges (84.0%), research & development (5.4%), airfields (3.4%), barracks & camps (2.5%), storage & supply depots (1.6%), and other (3.0%). These are largely managed by the Defence Infrastructure Organisation.
Example Output: What organization do airfields manage?

Example Input: Passage: By 3400 BCE, the Sahara was as dry as it is today, due to reduced precipitation and higher temperatures resulting from a shift in the Earth's orbit. As a result of this aridification, it became a largely impenetrable barrier to humans, with the remaining settlements mainly being concentrated around the numerous oases that dot the landscape. Little trade or commerce is known to have passed through the interior in subsequent periods, the only major exception being the Nile Valley. The Nile, however, was impassable at several cataracts, making trade and contact by boat difficult.
Example Output:
When did the Sahara become accessible to humans?