Answer:
The correct answer is option D, that is, both disruptive selection and evolution of reproductive isolation.
Step-by-step explanation:
The phenomenon of the evolution of a novel species from a thriving ancestral species and at the same time both continue to live in a similar geographical area is termed as sympatric speciation. Due to reproductive isolation of the population of species that were thriving in a similar habitat, the phenomenon of sympatric speciation results.
On the other hand, sympatric speciation also results due to disruptive selection as in the process the extreme kind of individuals within the population are favored over the hybrids.