Endemic species are:

A species is called "endemic" to a region when its entire natural population occurs only within that specific geographic area and is not found living in the wild anywhere else. Endemism is a statement about the geographic RESTRICTION of a species' natural distribution — it says nothing by itself about how many individuals survive or whether the species is threatened.

Applying this to the question: the option describing plants and animals found exclusively in a particular geographical area matches this definition exactly, so that is the defining description of an endemic species.

• Plants and animals that are common and distributed throughout the globe describe the opposite of endemism — a widespread, cosmopolitan distribution across many regions.

• Wild species under threat of extinction describes conservation status (endangered or vulnerable), an entirely separate classification from geographic distribution — a species can be endemic without being endangered, and endangered without being endemic.

• Wild species rescued from poachers describes an anti-poaching conservation activity, which has no bearing on how a species' natural geographic range is defined.

This matches standard usage in ecology: for example, the Nilgiri tahr is endemic to the Western Ghats because its entire wild population is restricted to that mountain range — confirming that endemism is fundamentally about WHERE a species naturally occurs, not how many individuals remain or how it is protected.