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]: The enzyme LCAT catalyzes the formation of an ester from this compound. Intermediates in the synthesis of this compound include squalene [SKWAY-leen] and mevalonate [muh-VAL-uh-nate], the latter of which is produced by HMG-CoA reductase. Vitamin D is formed from the 7-dehydro form of this compound, which reduces membrane fluidity. This compound, which is transported to the liver by high-density lipoprotein, is linked to heart disease. For 10 points, name this compound whose amount in the blood is lowered by statins such as Crestor and Lipitor.
[EX A]: Science

[EX Q]: The Clausius-Clapeyron equation assumes the change in this to be zero. Because this quantity is most useful when the substance in question is both isothermal and isobaric, a different quantity is used for explosive substances. An equation partially due to the namesake of this quantity gives the temperature dependence of this quantity for an ideal gas. A zero change in this quantity for a system implies that the system is in equilibrium, but a negative value for this quantity implies that a reaction is spontaneous. One may derive this by utilizing the Legendre transform on the internal energy of a system. For ten points, name this state function named for its American inventor, which measures the maximum amount of work attainable from a system, defined as enthalpy minus the product of temperature and entropy.
[EX A]: Science

[EX Q]: The most precise measurement for this quantity has come from the magnetic moment of the electron. For an electromagnetic interaction with n vertices, the amplitude for the interaction is proportional to this constant to the nth power. The square of this number is the ratio of the Hartree energy to the rest mass of the electron, and it is the ratio of the classical velocity in the ground state of the Hydrogen atom to the speed of light. The probability of a mechanism of an electromagnetic interaction involving n virtual photons is proportional to this constant to the 2n power, which in Quantum Electrodynamics indicates that this is the coupling constant for electromagnetic interactions. For 10 points, name this dimensionless constant in quantum mechanics, famously miscalculated by a numerological argument by Eddington, which is approximately one over 137.
[EX A]:
Science