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.

Q: Passage: Tourism is a major industry owing to the city's climate, its beaches, and numerous tourist attractions such as Balboa Park, Belmont amusement park, San Diego Zoo, San Diego Zoo Safari Park, and SeaWorld San Diego. San Diego's Spanish and Mexican heritage is reflected in the many historic sites across the city, such as Mission San Diego de Alcala and Old Town San Diego State Historic Park. Also, the local craft brewing industry attracts an increasing number of visitors for "beer tours" and the annual San Diego Beer Week in November; San Diego has been called "America's Craft Beer Capital."

A: What type of tours attract a large number of visitors to San Francisco?
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Q: 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.

A: What is formed when molten metal is separated from other substances?
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Q: Passage: In other contexts the term does not necessarily have pejorative overtones and may even be complimentary when used, in areas where innovation is welcome, of ideas that are in fundamental disagreement with the status quo in any practice and branch of knowledge. Scientist/author Isaac Asimov considered heresy as an abstraction, Asimov's views are in Forward: The Role of the Heretic. mentioning religious, political, socioeconomic and scientific heresies. He divided scientific heretics into endoheretics (those from within the scientific community) and exoheretics (those from without). Characteristics were ascribed to both and examples of both kinds were offered. Asimov concluded that science orthodoxy defends itself well against endoheretics (by control of science education, grants and publication as examples), but is nearly powerless against exoheretics. He acknowledged by examples that heresy has repeatedly become orthodoxy.

A:
What term always has negatie overtones?
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