0. The biggest reserves of thorium are in:
India has the largest reserves of thorium in the world, primarily found in the monazite sands of its coastal regions, especially:
Kerala
Tamil Nadu
Odisha
Andhra Pradesh
Thorium is considered a potential nuclear fuel, and India has invested heavily in thorium-based nuclear energy programs as part of its three-stage nuclear power plan.
Option A: India – Correct. Holds about 25–30% of the world’s thorium reserves.
Option B: China – Has some thorium, but not the largest reserves.
Option C: The Soviet Union – No longer exists as a country; individual countries like Russia have smaller thorium deposits.
Option D: U.S.A – Has thorium deposits, especially in states like Idaho, but less than India.