Answer:
Option B, numbers of all taxa will increase with time
Step-by-step explanation:
As per the Darwin's theory of "Natural selection" , the fittest among all species will be able to survive.
In order to become the fittest, all the species try to evolve and adapt traits or characteristics that make them able to cope up with the changing surrounding environment.
Each evolved species constitutes a new taxa and hence in future taxa number will increase.
Thus, option B is correct.