Interdisciplinary knowledge is significant in the UPSC exam as it allows candidates to make connections across different subjects. Understanding concepts from Economics, Polity, and Society can enhance analytical skills and provide a broader perspective on questions. It helps in tackling case studies and essay topics effectively, as these often require insights from multiple domains. Moreover, interdisciplinary knowledge reflects a candidate's versatility and preparedness, qualities that examiners value. Embracing this approach not only aids in the examination but also cultivates well-rounded future administrators equipped for complex governance challenges.