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 of these organic compounds is converted to an alkene by a diorganochromium compound in the Takai olefination. Compounds may be reduced to this functionality via the use of DIBAL-H (die-bahl aitch), and alkynes are formed by a reaction of these compounds with tetrabromomethane and triphenylphosphine named for Corey and Fuchs. When these organic compounds lack a hydrogen atom in the alpha position, their disproportionation can be induced by a base in the Cannizzaro reaction. These organic compounds are oxidized to carboxylic acids by a diamminesilver (I) complex, leading to the precipitation of metal onto the inside of the vessel, giving the positive "silver mirror" result of the Tollens test. For 10 points, name this special class of ketones with one R group being just hydrogen.
Science

Cities on its shores include Kibwesa, Wapembe, and Mpala, and the Mushara, Murembwe and Dama end in it. A source of great biodiversity, its namesake sardine is an important food source for locals. Despite its depth, the lower regions are mysteriously only a few degrees colder than the surface. In rainy years water from it flows into the Lukuga River and then into the Lualaba. John Speke and Richard Burton were the first two westerners to find it, and Henry Stanley found David Livingstone at Ujiji on its shores. It felt a 6.5 magnitude earthquake in 2005 due to a shift in the fault that is responsible for the Great Rift Valley, and it borders four countries including Burundi and Tanzania. FTP, name this member of the African Great Lakes, the world's second biggest lake by volume.
Social Science

A Grothendieck topology defines a sieve as a collection of subsets of a set with this property that themselves have this property. The Lindehf condition for a space requires every cover of this type to have a countable subcover. Generally, two points are "separated" if each point is contained in a set of this type that doesn't contain the other. In the particular point topology, all sets that contain an arbitrary point are of this type. A subset U of a metric space has this property if every point therein has a neighborhood inside U. Sets have this property in R^n when every point is an interior point. For 10 points, name this topological property, possessed by a set if its complement is closed.

Science