Where was the historic convention on biological diversity held?

Which one of the following is an example of $ex \, situ$ conservation?

In $2002$,in . . . . . . the World Summit on Sustainable Development was held.

When was the Biosphere Reserve programme started in India?

$A$: Biosphere reserves are also included under the ex-situ conservation strategies.
$R$: Cropping and grazing are allowed in the transition zone of biosphere reserve.

Define/Explain: Cryopreservation.