Match the following with respect to different categories of red list. Choose the correct option.

	Column-I		Column-II
i.	Extinct	a.	species whose members survive only in captivity.
ii.	Extinct in wild	b.	Rapid population decline of 50% to more than 70% over the previous 10 years.
iii.	Endangered	c.	species in which the last individual has died.
iv.	Vulnerable	d.	Rapid population decline of 30% to more than 50% over the previous 10 years.

Apply the relevant identity from the chapter and substitute the values established in the previous step, keeping the original constraint in view.

Use the simplified expression to isolate the unknown, then plug the result back into the question setup to confirm the working is internally consistent.

Cross-check against a boundary or limiting case. Both the dimensional balance and the qualitative behaviour at the extreme should agree with the candidate answer.

Combine the steps above to identify the correct option. The remaining choices each fail at least one of the consistency, dimensional, or boundary checks.