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: Although anthropologists worldwide refer to Tylor's definition of culture, in the 20th century "culture" emerged as the central and unifying concept of American anthropology, where it most commonly refers to the universal human capacity to classify and encode human experiences symbolically, and to communicate symbolically encoded experiences socially.[citation needed] American anthropology is organized into four fields, each of which plays an important role in research on culture: biological anthropology, linguistic anthropology, cultural anthropology, and archaeology.
Example Output: Who's definition of culture did anthropologists reject?

Example Input: Passage: When a molten metal is mixed with another substance, there are two mechanisms that can cause an alloy to form, called atom exchange and the interstitial mechanism. The relative size of each element in the mix plays a primary role in determining which mechanism will occur. When the atoms are relatively similar in size, the atom exchange method usually happens, where some of the atoms composing the metallic crystals are substituted with atoms of the other constituent. This is called a substitutional alloy. Examples of substitutional alloys include bronze and brass, in which some of the copper atoms are substituted with either tin or zinc atoms. With the interstitial mechanism, one atom is usually much smaller than the other, so cannot successfully replace an atom in the crystals of the base metal. The smaller atoms become trapped in the spaces between the atoms in the crystal matrix, called the interstices. This is referred to as an interstitial alloy. Steel is an example of an interstitial alloy, because the very small carbon atoms fit into interstices of the iron matrix. Stainless steel is an example of a combination of interstitial and substitutional alloys, because the carbon atoms fit into the interstices, but some of the iron atoms are replaced with nickel and chromium atoms.
Example Output: What is formed when molten metal is separated from other substances?

Example Input: Passage: In 2007, RIBA called for minimum space standards in newly built British houses after research was published suggesting that British houses were falling behind other European countries. "The average new home sold to people today is significantly smaller than that built in the 1920s... We're way behind the rest of Europeeven densely populated Holland has better proportioned houses than are being built in the country. So let's see minimum space standards for all new homes," said RIBA president Jack Pringle.
Example Output:
What did the Royal Institute oppose in order to keep up with housing in mainland Europe?