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]: proteins bind one end of these structures and help inhibit a process called "catastrophe. " These structures can have persistence lengths of 3-4 mm, which is several orders of magnitude higher than the average cellular diameter. These structures can be severed by katanin. Drugs such as paclitaxel stabilize these structures and prevent their depolymerization, where colchicine prevents its dimeric subunits from coming together. Shortening of these structure at the kinetochore ends of the spindle apparatus helps chromosomes walk towards poles during mitosis and meiosis. For 10 points, identify these structures which are components of the cytoskeleton and which are made of tubulin proteins.
[A]: Science


[Q]: Late in his reign, this king put down revolts led by Ashina of Elam and Nidintu-Bel of Babylon. Other rebellions during his rule include one caused by his brother Artaphernes's response to a request for help from Naxos, leading to an uprising by Aristagoras of Miletus. This man also defeated the Margian leader Frada, as well as a usurper called Gaumata who may have impersonated his brother Bardiya. Those feats are recorded in the trilingual Behistun Inscription, and as king, this man notably succeeded the conqueror of Egypt, Cambyses II. He is best known, however, for ordering an invasion that ended with a decisive defeat by the general Miltiades at the Battle of Marathon. For 10 points, identify this Persian ruler, the father of Xerxes I.
[A]: History


[Q]: During this dynasty, Prince Li Shimin ordered his brothers' deaths in the Xuanwu Gate Incident. One of its rulers' hatred of Yeon Gaesomun prompted one of its invasions of Goguryeo. This dynasty saw the appointment of jiedishi lords, a notable one of whom captured Luoyang in a power struggle with Yang Guozhong. The aftermath of that rebellion by An Lushan influenced Du Fu's poetry during this dynasty. One monarch of this dynasty apocryphally ordered court visitors to give oral sex and started out as one of Emperor Taizong's concubines. For 10 points, name this Chinese dynasty that succeeded the Sui and established a sprawling civil service under Empress Wu.
[A]:
History