Explain as simple as possible ? : how does the genetic code provide evidence of the common ancestry of all life?

The genetic code conserved most of then times in every organism from bacteria to humans. However, there is no rule that says the genetic code must work like that exactly. So, if for example different species "appear out of thin air" then we would expect them to have different genetic codes. The most plausible way to explain the fact that the genetic code works the same for every organism is that it was passed down from the first common ancestor of all life.

The correct answer:   [c]:   "cell phone call" .