Correct Option: D

Exobiology is the branch of science that deals with the possibility and likely nature of life on other planets or in space. The primary goal of exobiological research is to reach a better understanding of the processes leading to the origin, evolution and distribution of life on Earth or elsewhere in the universe. Exobiological activities include comparison of the overall pattern of chemical evolution of potential precursors of life, in the interstellar medium, and on the planets and small bodies of our solar system, tracing the history of life on Earth back to its roots, deciphering the environments of the planets in our solar system and of their satellites