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]: Chan and Kim at Penn State discovered that crystals can display this phenomenon. One instance of this phenomenon is distinguished by either an A or B phase, and is anisotropic. Some materials that exhibit this phenomenon display a 30 nm Rollin film, and their movement sometimes displays the Onnes Effect. Landau theorized that quantum sound waves are responsible for this effect, which he posited occurs below the lambda point. For 10 points, name this property notably displayed by helium, when a liquid or gas displays no resistance to flow.
[EX A]: Science

[EX Q]: One protein that binds to this protein also binds to proline-rich sequences in the membrane proteins Vasp and Mena, and another is knocked out in the singed mutant. Phosphatidyl-inositol-4,5-bisphosphate regulates the binding of vinculin to both talin and this other protein, whose function is performed by nematode Major Sperm Protein in the only (*) eukaryotic cells known to lack one form of it. In addition to the aforementioned profilin and facsin, severin and gelsolin bind to this protein and sever it. Two toxins often used to study it are cytochalasins and phalloidin. Thymosin 4 sequesters this protein, which undergoes treadmilling because the critical concentration at its (+) and (-) ends is not the same. This protein consists of G monomers which polymerize into F filaments, which make up the microfilaments of the cytoskeleton. For 10 points, name this protein that forms cross-bridges with myosin in muscle cells.
[EX A]: Science

[EX Q]: After this deity was impregnated by Iasion, she gave birth to the god of wealth Plutus. She was worshiped in Arcadia as a woman with the head of a horse because Poseidon turned into a stallion to rape her. The Eleusinian Mysteries were held in honor of this goddess and her daughter. She gave Triptolemus a winged chariot pulled by snakes to help him teach the world agriculture during her search for her (*) daughter, who was abducted into the underworld by Hades. For 10 points, name this mother of Persephone, the Greek goddess of grain and the harvest.
[EX A]:
Social Science