A single living thing that can breed/produce fertile offspring

A species is often defined as a group of organisms that can reproduce naturally with one another and create fertile offspring.

Explanation:

if this helps brainliest ?

mammals

A species is often defined as a group of organisms that can reproduce naturally with one another and create fertile offspring. However, the classification of a species can be difficult—even riddled with controversy.

pregnancy happens more and more

i am positive it is c. condensing but i may be wrong