Question

An _____ is the end of a group of organisms, usually a species. Five of them occurred throughout geologic time.

a) Extinction
b) Evolution
c) Speciation
d) Extirpation

Answer 1

An a) extinction is the end of a group of organisms, typically a species. There have been five mass extinctions in geological history where major groups of species were eliminated. Hence, a) is correct.

Step-by-step explanation:

An extinction is the end of a group of organisms, usually a species. Throughout geologic time, there have been five mass extinctions where major groups of species were eliminated.

Extinctions occur when the last individual of a species dies out, often due to environmental changes. For example, the famous extinction event at the end of the Cretaceous period led to the extinction of dinosaurs and many other species.