Organisms that originated in a certain geographic region and can only be found in that region are said to be

a. keystone species
b. climax organisms
c. invasive
d. endemic

Organisms that originated in a certain geographic region and can only be found in that region are said to be endemic.

Explanation:

Endemic organisms are taxonomic species (plants and animals) which originates and distributed only in specific geographic regions. This state of evolution is called endemism.

They are said to be native or indigenous to that particular region which can be an ecological habitat, an entire nation, an island, a mountain range etc. Certain parts are known for majority of their species being endemic like St. Helen Island, New Caledonia Island, Hawaiian Islands, Southern regions of Africa, and Australia.

The species becomes endemic to a particular region because of the presence of certain bio-geographical environmental qualities of that habitat which are favorable to that species.

When these conditions become unfavorable, then species becomes restricted leading to endangerment or extinction of the species.

Examples:

b) the inside picture would look at a very high temperature in a very low ph