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: An alloy is a mixture of metals or a mixture of a metal and another element. Alloys are defined by metallic bonding character. An alloy may be a solid solution of metal elements (a single phase) or a mixture of metallic phases (two or more solutions). Intermetallic compounds are alloys with a defined stoichiometry and crystal structure. Zintl phases are also sometimes considered alloys depending on bond types (see also: Van Arkel-Ketelaar triangle for information on classifying bonding in binary compounds).

SOLUTION: What is always a mixture of metal and other elements?

PROBLEM: Passage: Before the French and Indian War, the Appalachian Mountains laid on the indeterminate boundary between Britain's colonies along the Atlantic and French areas centered in the Mississippi basin. After the French and Indian War, the Proclamation of 1763 restricted settlement for Great Britain's thirteen original colonies in North America to east of the summit line of the mountains (except in the northern regions where the Great Lakes formed the boundary). Although the line was adjusted several times to take frontier settlements into account and was impossible to enforce as law, it was strongly resented by backcountry settlers throughout the Appalachians. The Proclamation Line can be seen as one of the grievances which led to the American Revolutionary War. Many frontier settlers held that the defeat of the French opened the land west of the mountains to English settlement, only to find settlement barred by the British King's proclamation. The backcountry settlers who fought in the Illinois campaign of George Rogers Clark were motivated to secure their settlement of Kentucky.

SOLUTION: When did the French and Indian war begin?

PROBLEM: Passage: The Digimon series has a large number of video games which usually have their own independent storylines with a few sometimes tying into the stories of the anime series or manga series. The games consists of a number of genres including life simulation, adventure, video card game, strategy and racing games, though they are mainly action role-playing games. The games released in North America are: Digimon World, Digimon World 2, Digimon World 3, Digimon World 4, Digimon Digital Card Battle, Digimon Rumble Arena, Digimon Rumble Arena 2, Digimon Battle Spirit, Digimon Battle Spirit 2, Digimon Racing, Digimon World DS, Digimon World Data Squad, Digimon World Dawn and Dusk, Digimon World Championship, and Digimon Masters.

SOLUTION:
What did the Digimon series only have a few of?