Answer:
The correct answer will be- Speciation.
Explanation:
Speciation represents the process of formation of new species formed from the ancestral species.
The process of speciation takes place only when the new species are reproductively isolated that is they no longer mate and diverge independently.
The isolation could be geographical like mountains and rivers and form species through allopatric speciation or the sympatric speciation which forms new species from an ancestral species without any geographical separation.
Thus, speciation is the correct answer.