Ex-situ Conservation: This involves protecting an endangered species outside its natural habitat. Cryopreservation is a technique where biological materials (like seeds, embryos, or gametes) are stored at extremely low temperatures (usually in liquid nitrogen at -196°C) to preserve them for long periods. In-situ Conservation (Options a, b, d): Wildlife Sanctuaries, Biosphere Reserves, and National Parks are all methods of protecting species within their natural environments.

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