Select the correct term for the following definitions (i, ii, iii, iv).
(i) The taxon is liable to become extinct if not allowed to realise its full biotic potential by providing protection from exotic species/human exploitation/ habitat deterioration/ depletion of food.
(ii) The taxon has been completely eliminated or died out from earth, e.g., Dodo.
(iii) The taxon is facing a high risk of extinction in the wild in the near future due to decrease in its habitat, excessive predation or poaching.
(iv) They are species with naturally small populations, either localised or thinly scattered, which are always at risk from pests/pathogens/predators/exotic species.