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.

[EX 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.
[EX A]: Science

[EX Q]: A maximum independent set for this data structure can be found in linear time by adding alternating levels. In this structure, any two vertices or nodes must be connected by a single simple path, and thus it is connected and acyclic. By using (*) union-find with disjoint sets, one type of this structure containing all the vertices of a connected graph can be constructed. One variety of this data structure can be used to easily implement a binary search. This structure also comes in red-black and self-balancing-binary varieties. For 10 points, identify this data structure from computer science, a hierarchical graph in which "leaf" nodes ultimately flow from a "root" node.
[EX A]: Science

[EX Q]: In this religion, the last step a devotee needs to perform to reach a union with God is known as Sach Khand. Practitioners of this religion engage in meditation called simran. One of the leaders of this religion emphasized that metal bracelets and curved swords are two of the five key requisites for an ideal devotee. Gobind created the five (*) "K"s for the Khalsa branch of this religion. Devotees often travel to the Golden Temple in Amritsar to pay their respects. For ten points, name this Indian religion, practiced mainly by Punjabis and founded by Guru Nanak.
[EX A]:
Social Science