Prior knowledge in subjects is crucial for tackling the UPSC exam, as it provides a solid foundation for understanding complex topics. A robust grasp of fundamental concepts across disciplines like history, geography, polity, and economy enables candidates to draw connections and develop informed analyses. Familiarity with core subjects facilitates quicker comprehension of related current affairs, enhancing the applicability of theoretical knowledge. This prior knowledge is significant not only for answering direct questions but also for showcasing analytical and critical thinking abilities during the interview process.