In this task you will be given a text passage from a trivia quiz. You should choose the category this question belongs to from these categories: History, Science, Social Science, Fine Arts, Literature. You can only choose one category, so if in doubt, please choose the closest match.

Q: Halogen addition to them creates a mixture of a 1-2 and 1-4 addition product. One preparation of them involves butane undergoing thermal dehydration. Another synthesis of the conjugated variety of this chemical group involves elimination of unsaturated alcohols and alkyl halides. They include a number of useful reagents, including ones named for Chan, Dane, Brassard, Rawal, and Danishefsky. In addition to the conjugated variety, they also occur in isolated and cumulated varieties. Conjugation energy guarantees that the conjugated form is the most stable. For ten points, what is this organic functional group whose 1,3 variety are a principal reactant in the Diels-Alder reaction, and which is characterized by a pair of double bonds.

A: Science
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Q: The yield of these compounds can be increased through ball milling of some of their components, and one mode of operation of these compounds proceeds through a mechanism called enantiomorphic site control. A process for the operation of these compounds that proceeds through migratory insertions and obeys the "principle of least nuclear motions" was developed by Cossee and Arlman. Compounds such bis(cyclopentadienyl)titanium chloride and bis(indenyl)zirconium dichloride, known as metallocenes, have been developed as an alternative to the traditional compounds of this type. Those traditional initiators include vanadium trichloride and triethylaluminum, and the product of the application of these compounds to alkenes can result in syndiotactic, isotactic, or atactic products. For ten points, identify these stereoselective compounds used to initiate polymerization, named for a German and an Italian chemist.

A: Science
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Q: This monarch established a legal framework for his realm with the Ordinance of Blois. This ruler was inspired to go on religious pilgrimages by his minister, Emond Auger. During his reign, Protestant worship was restricted to just one suburb of each town through the Peace of Bergerac. A succession crisis developed after this childless king's brother and leader of the Malcontents, Francis, duke of Anjou, died. He succeeded (*) Sigismund II as King of Poland-Lithuania. During the Day of the Barricades, he was driven out of Paris by Henry of Guise. He was ultimately assassinated by a monk named Jacques Clement, making him the last Valois king. For 10 points, name this French king who presided over the Saint Bartholomew's Day Massacre.

A:
History
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