Detailed Instructions: 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.
Q: In topological insulators, one version of this effect gives rise to a defect-resistant current induced by spin-orbit coupling. In graphene, this effect is shifted by one half, giving rise to an anomalous minimum of the relevant quantity, which can allow for ballistic transport. A more complex version of it was discovered in gallium arsenide and can be explained by Laughlin quasiparticles; this is referred to as the fractional version. This effect can be understood in terms of partial filling of Landau levels and has characteristic "plateaus", and it yields numbers called filling factors. Discovered by Klaus von Klitzing when studying a two-dimensional electron gas, for 10 points, identify this effect in which conductivity in a strong magnetic field is quantized.
A:
Science