This study examines the determinants of Indian 10-year government securities (G-Sec) yields from February 2015 to December 2025 using the Autoregressive Distributed Lag (ARDL) bounds testing framework. Based on 131 monthly observations sourced from Bloomberg, RBI, MOSPI, and FRED, the analysis explores the influence of fiscal deficit, monetary policy, inflation, exchange rate dynamics, and global risk factors on sovereign bond yields within the NAVI (Non-linear, Accelerated, Volatile, Interconnected) paradigm. The Pesaran-Shin-Smith bounds test confirms long-run co-integration (F = 3.85, significant at 5%). The US 10-year Treasury yield is identified as the dominant long-run driver with a near-unity coefficient (0.999), while the VIX index exerts a significant negative effect, consistent with a domestic flight-to-safety mechanism. The fiscal deficit, although theoretically central, is statistically insignificant in the full-sample ARDL, indicating that active debt management by the RBI absorbs the crowding-out channel. Sub-period analysis demonstrates that the repo rate pass-through declined from 0.60 pre-COVID to near zero post-COVID. These findings have implications for monetary-fiscal coordination and sovereign debt management.