Why should mutation be necessary criterion, along with reproduction & metabolism, ......?

Question

I need help answering this essay question for my Env. Science class.... Why should mutation be necessary criterion (along with reproduction and metabolism) for the indication of life within a system?

Answer 1

Because mutation is a necessary component of evolution, and evolution is the only know method by which complex life can exist.

Answer 2

without mutation and variation, there would not be a diversity of phenotypes which is needed for some members of the species to adapt to the environment.

Answer 3

because without mutation, there would be no evolution, no way of advancing the species.

reproduction is obvious, we need MORE BABIES