The correct answer is option (2), because the flippers of the Penguins and Dolphins perform similar function but they are not anatomically similar structures. This is example of analogous structures. - Option (1) is incorrect as natural selection is a key mechanism of evolution. - Option (3) is incorrect as divergent evolution results in the formation of homologous structures. - Option (4) is incorrect as adaptive radiation is the process of evolution of different species in a given geographical area starting from a point and literally radiating to the other areas of geography.