The guy asking the question did not appear to understand anything about evolution - not even the basic concept. You would have to take him back to the most basic of ideas, and start him again from ground up. Even then, I suspect he would reject the beginnings, and continue to ask dopey questions.
The thing I wonder is if the guy was just plain stupid, or was refusing to learn. Some (most?) anti-evolutionists are like that. You cannot teach them even the most basic concepts, since they reject them and refuse to absorb any knowledge at all about the process.
For every human action, there is a rationalisation and a reason. Only sometimes do they coincide.