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.

One character in this work pretends to sing a fashionable song from "The Vain Precaution" in a scene that ends in the quintet "Buona Sera". This opera's tenor pretends to be a drunken soldier when he meets the servant girl Berta, while in the aria "Calumny is a little breeze", Doctor Bartolo receives advice from Don Basilio. Its popular overture was intended for its composer's Aureliano in Palmira, while its first act sees Rosina describe her love for Lindoro in "Una voce poco fa". This opera's title character first appears singing the aria "Largo al Factotum" and aids Count Almaviva in wooing Rosina. For 10 points, name this opera about Figaro, composed by Gioacchino Rossini.
Fine Arts

Seas of calcite predominate during times of low concentration of this element. The NIMS probe discovered that Ganymede has a sulfate of this element, which is also used to treat eclampsia. Its molten form is used to make metallic titanium in the Kroll process. The active site of rubisco contains a carbamylated lysine attached to an ion of this element. Its cationic form is used to stabilize the product of PCR, and it is also prevalent in certain reagents in a Schlenck equilibrium. It is found in Grignard reagents as well as coordinated to the porphyrin ring of chlorophyll. For 10 points, name this element with atomic number 12 and symbol Mg.
Science

One alternative to this reaction uses diorganochromium and is named for Takai, while one variant is further modified by using KHMDS and is named for Still. The ability of one intermediate to interconvert is called stereochemical drift, and one modification uses a sulfur-containing compound in order to create epoxides. In addition to the Corey-Chaykovsky reaction, and ester version of this reaction was developed by Horner, Wadsworth, and Emmons, while the erythro betaine can be converted to the threo version using phenyllithium in a version named for Schlosser. The formation of an oxaphosphetane drives, FTP, this reaction which uses a phosphonium ylide to create alkenes from carbonyls, named for a German.

Science