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 reaction to prepare these compounds adds diazomethylphosphonate esters to aldehydes under basic catalysis and generates vinyl-diazo intermediates. Along with aldehydes, these compounds are the degradation products of alpha, beta-epoxy tosylhydrazones in the Eschenmoser fragmentation. A coupling involving both palladium and copper catalysis, in which these compounds react with aryl halides, is the Sonogashira reaction. These compounds react with azides to form triazole rings in a well-known click-chemistry reaction, and terminal ones can be deprotonated by sodium amide. They are reduced to cis-alkenes by the poisoned Lindlar catalyst. This functional group is composed of two sp-hybridized carbons. For 10 points, name this functional group consisting of a carbon-carbon triple bond.
Science

Gravitational redshift was measured by Pound, Rebka, and Snider in Harvard's Jefferson Tower using this technique to detect a frequency shift of order one part in ten to the 14th. It can be used for precise studies of the Zeeman effect in nuclei. Iron 57 and tin 119 are two of the isotopes used in this type of spectroscopy due to narrow linewidths in their transitions. Before this technique, the large size of Doppler shifts relative to transition widths made nuclear spectroscopy problematic. It was discovered by its namesake when he was a graduate student at the Munich University of Technology. FTP, what is this effect in which a crystal lattice reduces recoil energy
Science

A failed naval expedition led by this country's Blanco Encalada resulted in the 1837 Treaty of Paucarpata, while its 1925 Constitution began its Presidential Republic period. This modern day country was captured in a campaign led by Pedro de Valdivia; that campaign saw fighting against its native Araucanian or Mapuche Indians. This country's Patria Vieja period of independence was ended at the Disaster of Rancagua. Its independence campaign was led by men like the Carrera Brothers and Bernardo O'Higgins, and the 19th century saw the flourishing of its free port Valparaiso. For 10 points, name this South American country led in the 20th century by Salvador Allende and Augusto Pinochet.

History