Describe  various methods used in ‘In situ conservation’

Which is an example of ex-situ conservation?

Modern ex situ conservation includes

Conservation of plant diversity is mostly a / an

Which one of the following is not observed in biodiversity hot spots?

The fast dwindling $....A... $$\;\%$ forest is estimated to produce $....B... $$\;\%$ percent of the total oxygen in earth’s atmosphere.