https://www.123articleonline.com/rss/author/362233/discrete-iasArticles written by Discrete ias from 123ArticleOnline.comen-usCopyright (c) 123ArticleOnline.com All rights reserved. https://www.123articleonline.com/articles/1320664/how-to-choose-optional-subject-for-upsc . Interests and Educational Background of the Postgraduate Student: Determine your interest in the subject by studying the NCERT grade level (preferably in grades 11 and 12), completing the supplementary syllabus on the subject, and your level of comfort in reading the subject.