Q.What is a biosphere reserve, and what purpose does each of its three zones -- the core, the buffer and the transition zone -- serve?

In-situ conservation protects species within their natural habitat; National Parks, sanctuaries and biosphere reserves are examples.

In-situ ('on site') conservation involves protecting species in their own natural habitat, allowing them to live and reproduce under natural conditions — examples include National Parks, Wildlife Sanctuaries and Biosphere Reserves. Ex-situ ('off site') conservation, by contrast, protects threatened species out …

A Botanical Garden is an ex-situ (off-site) conservation method, unlike the other three in-situ options.

In-situ conservation protects species within their own natural habitat - examples include Sanctuaries, National Parks, and Biosphere Reserves.

Ex-situ conservation protects species outside their natural habitat, in controlled/artificial settings - examples include Botanical Gardens, zoological parks, seed banks, gene banks, and tissue-culture/cryopreservation facilities.

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Zoological parks fall under ex-situ conservation, since they keep animals away from their natural habitat, unlike the other three options.

In-situ conservation protects species within their own natural habitat and ecosystem -- Biosphere Reserves protect large representative ecosystems, Wildlife Sanctuaries protect specific species/habitats with some regulated human activity allowed, and National Parks strictly protect entire natural ecosystems with minimal human interference; all three keep organisms living in their natural surroundings. A Zoological Park, however, houses animals in an artificial, controlled en …

Sundarlal Bahuguna is famously associated with the Chipko Movement — the answer is (c).

The Chipko Movement (Uttarakhand, 1970s) was a forest-conservation movement in which local people, especially women, embraced (hugged) trees to stop contractors from cutting them down ('Chipko' means 'to hug/stick'). Sundar Lal Bahuguna was one of its most prominent leaders (along with Chandi Prasad Bhatt). …