Indian nuclear fuel strategy: fast breeder reactors are especially relevant to India primarily because the country has large deposits of which fertile resource?

Introduction / Context:
India's three-stage nuclear power programme leverages indigenous resource endowments. The country has relatively modest uranium reserves but very large thorium reserves. Fast breeder and associated fuel-cycle strategies are designed to utilise fertile materials efficiently and expand fissile inventories over time.

Given Data / Assumptions:

• India has abundant thorium-bearing monazite sands along certain coasts.
• Fast reactors can breed fissile isotopes from fertile nuclides.
• Programme aims to improve resource utilisation and energy security.

Concept / Approach:
A fertile isotope becomes fissile after neutron absorption and subsequent nuclear transformations. In breeder strategies, U-238 can breed to Pu-239, and thorium-232 can breed to U-233. India’s strategy exploits initial reactors to generate plutonium for fast breeders, which in turn support the thorium cycle to realise long-term energy independence.

Step-by-Step Solution:
Recognise resource endowment: thorium is abundant in India compared with uranium.Breeding pathways: Th-232 → U-233 in appropriate reactor/fuel cycles.Therefore, fast-breeder-related development aligns with tapping large thorium reserves.

Verification / Alternative check:
Policy documents and educational texts consistently describe India’s thorium-centric long-term plan, with fast reactors as a bridge to close fuel cycles and enable Th utilisation.

Why Other Options Are Wrong:
Plutonium: a produced fissile material, not a native large deposit.Uranium: India’s known uranium reserves are comparatively limited.None of these: contradicts the thorium reality.

Common Pitfalls:
Confusing breeder technology purpose (creating fissile material) with the inventory of naturally occurring deposits; assuming “plutonium deposits” exist—plutonium is man-made in reactors.

Final Answer:
thorium