Which one of the following biosphere reserves has UNESCO recognition?

Concept — A biosphere reserve is first designated by the national authorities of the country in whose territory it lies. That national designation is a separate step from UNESCO recognition: a site carries UNESCO status only after the country nominates it and the Man and the Biosphere (MAB) Programme’s International Co-ordinating Council admits it to the World Network of Biosphere Reserves (WNBR). The test here is therefore not "is this a biosphere reserve" but "has this reserve entered the WNBR".

Application — By the date of this 2013 paper India had designated 18 biosphere reserves of its own, but only nine of them had been admitted to the WNBR. Great Nicobar Biosphere Reserve — which this paper lists under the variant label "Greater Nicobar", while UNESCO’s own register spells it "Great Nicobar" — was admitted in May 2013 as India’s ninth entry on that network. Among the four names offered it is therefore the reserve that carried UNESCO recognition.

Cross-check — Each name against the WNBR register:

Answer — Great Nicobar, which this paper lists as "Greater Nicobar". Read against a present-day list the picture has moved on — Khangchendzonga was added to the WNBR in 2018 and Panna in 2020 — but for this 2013 question only Great Nicobar qualified.