Answer: The correct answer is-
A. Convergent evolution.
Convergent evolution can be described as evolutionary process by which organisms independently evolve similar characteristics due to adaptation in the similar environmental conditions.
As per the information given in this question, lung fishes adapted to terrestrial mode of life and considered as the ancestors of modern amphibians.
Amphibians also came into existence by adapting to terrestrial mode of habitat and they also developed lungs for respiration on land.
Thus, it represents the example of Convergent evolution.
Therefore, option A) is the right answer.
