Answer:
The correct answer is adaptive radiation.
Step-by-step explanation:
Adaptive radiation is a process of rapid diversification of an ancestral species into a large number of descendant species in a different environment with adaptive morphological and physiological traits.
Over 200 species of Marsupials mice, moles, flying squirrels and flying phalanger are found in Australia continent which was formed as a result of adaptive radiation from ancestral species to occupy the different niches of Australia.
Thus, adaptive radiation is the correct answer.