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: The Jenkins Orphanage was established in 1891 by the Rev. Daniel J. Jenkins in Charleston. The orphanage accepted donations of musical instruments and Rev. Jenkins hired local Charleston musicians and Avery Institute Graduates to tutor the boys in music. As a result, Charleston musicians became proficient on a variety of instruments and were able to read music expertly. These traits set Jenkins musicians apart and helped land some of them positions in big bands with Duke Ellington and Count Basie. William "Cat" Anderson, Jabbo Smith, and Freddie Green are but a few of the alumni from the Jenkins Orphanage band who became professional musicians in some of the best bands of the day. Orphanages around the country began to develop brass bands in the wake of the Jenkins Orphanage Band's success. At the Colored Waif's Home Brass Band in New Orleans, for example, a young trumpeter named Louis Armstrong first began to draw attention.

SOLUTION: What year was the Jenkins Orphanage closed?

PROBLEM: Passage: International investment and the wealth generated by wealthy tourists explain the high standard of living on the island. St. Barthélemy is considered a playground of the rich and famous,[citation needed] especially as a winter haven, and is known for its beaches, gourmet dining and high-end designers. Most of the food is imported by airplane or boat from the US or France. Tourism attracts about 200,000 visitors every year. As a result, there is a boom in house building activity catering to the tourists and also to the permanent residents of the island, with prices as high as €61,200,000 for a beachfront villa.

SOLUTION: How many homes are built each year?

PROBLEM: Passage: Together with caesium and gold (both yellow), and osmium (bluish), copper is one of only four elemental metals with a natural color other than gray or silver. Pure copper is orange-red and acquires a reddish tarnish when exposed to air. The characteristic color of copper results from the electronic transitions between the filled 3d and half-empty 4s atomic shells – the energy difference between these shells is such that it corresponds to orange light. The same mechanism accounts for the yellow color of gold and caesium.

SOLUTION:
How many grains of sand have a natural color that isn't gray?