GEOLOGY

Detailed explanation-1: -Organisms that have evolved to be so different from one another that they can no longer reproduce with each other are considered different species. All organisms that can reproduce with each other fall into one species.

Detailed explanation-2: -So the correct option is Species.

Detailed explanation-3: -A biological species is a group of organisms that can reproduce with one another in nature and produce fertile offspring.

Detailed explanation-4: -Interbreeding is key to the biological species concept, which defines a species as members of populations that can interbreed with each other to produce viable offspring. (To be considered “viable, ” the offspring must themselves be able to reproduce.)

Detailed explanation-5: -Species. A species is defined as a group of organisms capable of interbreeding and producing fertile offspring.