Answer:
a. occurs when there are fewer than 500 individuals within a population
Step-by-step explanation:
- An endangered species was a species that is the danger of the extinction an only significant part of this process remain and those species are at the likelihood of the extinction in the near future.
- As per the IUCN, the endangered species are those that have one that meets the criteria of about the 50 to 70% population which gets decreases over 10 years and has a total area that has than 5,000 km that is a population of the area less than 500 km.