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: 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.

A: Science
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Q: This man gives his name, along with that of Francis Sears, to a process in ultrasonic imaging for which the acoustic wavefronts act as optical gratings to diffract the light on either side of the central spot. The distance over which charge carriers in plasmas exclude electric fields via his namesake shielding is also known as his namesake length. With an assistant later famous in his own right for his rule for determining whether ring molecules would show aromatic properties, he developed a mathematical expression to explain characteristics of electrolytic solutions, the famous equation named for him and Erich Hckel. FTP name this man who also gives his name to the SI unit defined as about 3.3 x 10-30 Coulomb meters, which measures the molecular dipole moment.

A: Science
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Q: The title figures bow down to each other in this artist's etching Two Men Meet, Each Believing the Other to Be of Higher Rank from his Renaissance-inspired Inventions series. A heart forms the nose of an orange creature with a bird on its forehead in this artist's Cat and Bird. This artist included moons, flowers, and a stick figure with two faces and pink gloves in his painting Fish Magic. A sun (*) rises over a house painted in Pointillist style in this man's large composition, Ad Parnassum. While at the Bauhaus, this man wrote the Pedagogical Sketchbook. One of his best known works features several line-drawn birds standing on the title contraption. For 10 points, name this German-Swiss artist who combined Cubism and the art of children in works like Twittering Machine.

A:
Fine Arts
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