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]: Coombs tests detect these bodies bound to erythrocytes, and a technique that uses these entities is ELISA. These molecules have a namesake fold, in which two beta sheets are held together by amino acid charges. These adaptable molecules can somatically recombine in a process called V(D)J recombination and are also capable of changing isotype by altering conformation of their heavy chains. Like enzymes, they operate via a a so-called "lock-and-key" mechanism, as verified by Linus Pauling. FTP, name these characteristically y-shaped immune molecules exploited in vaccination and produced by B cells in response to specific antigens.
[A]: Science


[Q]: A territory invaded during this war asked to borrow gunpowder to salute a ship that had come to conquer it. One island invaded in this war had been overseen by the "Butcher" Weyler. An admiral in this war stated "You may (*) fire when you are ready," prior to beginning the Battle of Manila Bay. One battle in this "splendid little war" saw San Juan Hill charged upon by the Rough Riders and Teddy Roosevelt. Hearst's and Pulitzer's yellow journalism as well as the explosion of the USS Maine helped instigate this war. For 10 points, name this war which led to the capture of the Philippines, Puerto Rico, and Cuba by the United States.
[A]: History


[Q]: By averaging this quantity, the reduction of a certain intermolecular function to an angle-independent form for polar fluids can be performed in order to express conformal-solution theory. For liquid metals, the upper bound of this quantity can be obtained by the Gibbs-Bogoliubov inequality. It is equal to the negative product of Boltzmann's constant, temperature, and the natural log of the partition function. The change in this quantity is equal to the maximum work accompanying a process, and it is defined as internal energy minus the product of temperature and entropy. For 10 points, name this quantity symbolized by either A or F, a type of free energy named for a German scientist.
[A]:
Science