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]: Several of his early works, including such operas as Cleonice, Demofoonte, and Artaserse, were written with librettist Pietro Metastasio. He had begun composing an opera based on the Song of Roland, but the discovery that Niccolo Piccini was given the same libretto to work on sparked a rivalry in the Parisian press and motivated him to compose Armide. Collaboration with the librettist Calzabigi resulted in the composition of the ballets Semiramide and Don Juan, as well as an opera featuring the "Dance of the Blessed Spirits" and another in whose preface he declared his intent to "restrict music to its true office of serving poetry. " FTP, identify this German classical composer of "reform" operas such as Alceste and Orfeo et Euridice.
[EX A]: Fine Arts

[EX Q]: Vaihinger discussed the relation between Swedenborg and this man's concept of two worlds, in a commentary on this man's Dreams of a Spirit Seer. He proposed the creation of a league to mediate international disputes in his essay "Perpetual Peace," and defined ratiocination as the judgment of a predicate with its subject in "The False Subtlety of the Four Syllogistic Figures. " He defined his best-known concept by claiming that nothing can be called good without qualification "except a good will" in his Foundations of the Metaphysics of Morals. For 10 points, name this author of The Critique of Judgment and Critique of Pure Reason who created the "categorical imperative. "
[EX A]: Social Science

[EX Q]: A function that gives this quantity at a fixed level of utility is a "compensated" function. Changes in the curve that represents this quantity can be the result of the substitution and income effects. The Slutsky equation relates the Hicksian and Marshallian functions of this quantity. Giffen goods do not conform to the namesake law of this quantity. This quantity has a downward-sloping curve, and is defined as the willingness and ability to purchase a commodity or service. For 10 points, name this economic quantity, often paired with supply.
[EX A]:
Social Science