Why are you drawn to the area(s) of study you indicated earlier in this application? If you are "undecided" or not sure which Brown concentrations match your interests, consider describing more generally the academic topics or modes of thought that engage you currently.
Right now, I am preoccupied with the fundamental question, “Why?” It fascinates me, and subjects that take on answering that question are the ones that engage me most. So, if I were asked to choose a concentration today, I would likely pick either chemistry or political science. Although one is a natural science and one is a social science, they both focus on the “Why?” Chemistry explains why two liquids will or won’t mix, it explains why certain medicines react in particular ways, and it explains why the physical and material worlds operate the way they do. Political science attempts to explain why the world, and the nations that compose it, behave and exist in the fashion that they do. My eventual choice of concentration will be determined by whichever concentration’s “Why?” proves most interesting, and by whichever one I can best use to effect positive change in the world.