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]: When reacted with a nitrile, they produce an imine anion that can be hydrolyzed into a ketone, and they can cause nucleophilic ring opening of epoxides. Pouring a solution of them over dry ice followed by protonation results in carboxylic acids, which will not form addition products with these. One of their most common uses is reacting with aldehydes and ketones to form secondary and tertiary alcohols, respectively. Because they essentially act as carbanions, they can be protonated by weak acids to yield alkanes. FTP name these organometallic reagents that are formed by reacting an alkyl halide with magnesium, named for their French discoverer.
[A]: Science

[Q]: The earliest discovered writings on these were in the Hittite language and were authored by Kikkuli of Mitanni, while Gryson, an expert on these, helped Xenophon to write two treatises on the subject. Tupac Amaru II and Francois Ravaillac were both executed using four of these, and one of these named Incitatus was legendarily appointed as a Roman senator by Caligula. The Avars brought an invention that eased their use to Europe, and huge masses of these were instrumental in saving the French army at Eylau. Many cities were named after of these owned by Alexander the Great, Bucephalus. For 10 points, name these animals used to transport hussars and knights.
[A]: Literature

[Q]: His plays include The Living Room and The Complaisant Lover, and his short stories are collected in May We Borrow Your Husband. Switzerland is the setting for his Doctor Fischer of Geneva or the Bomb Party, while The Human Factor is set in South Africa and World War II. London is set setting for both The End of the Affair and The Ministry of Fear. FTP, identify this British author of The Quiet American and Brighton Rock, best known for such novels as Our Man in Havana and The Heart of the Matter.
[A]:
Literature