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.

Lin and Shu proposed the density-wave theory to explain how the structure of these entities is sustained. The most accurate method for measuring the distances to distant ones uses a relation between their maximum rotational velocity and absolute magnitude, which is known as the Tully-Fisher method. They are generally blue because of their high content of old stars, and one type of them features arms that emanate from each end of a namesake structure. They have discs like the lenticular type, but contain much more angular momentum than the elliptical type. FTP name these galaxies, some of which are barred, including the Milky Way.
Science

One of this author's works argues that "political emancipation" is compatible with religion, but blocks\n the fulfillment of "human emancipation." In another of his works, he developed his theory of "base and\n superstructure." This opponent of Bruno Bauer wrote that "Philosophers have only interpreted the world;\n the point is to change it" in his Theses on Feuerbach, as well as writing On the Jewish Question. Another\n of his works argues that a commodity attains value through the amount of labour put into it. For 10 points,\n name this German philosopher who, along with Engels, wrote Das Kapital.
Social Science

It reached its summit in its victories over Waldemar IV of Denmark, gaining in the Treaty of Stralsund a virtual monopoly in Scandinavia, but its hegemony was curbed by a Dutch defeat in 1441. The last diet was held in 1669, but this group never formally dissolved. Originating in a treaty between Lbeck and Hamburg in 1241, its goal was to obtain mutual security and exclusive trading rights for its members. FTP, identify this medieval German mercantile league.

History