What really is the greenest car?

iambuf questioned:

Hybrids certainly have the best gas mileage and, as far as I know, some of the cleanest emissions (for gasoline engines), but I have heard that with a life-logic breakdown the environmental trace is much privileged, frequently due to the battery.

I know riding a bike and compelling transit is exponentially ‘greener’ than driving, but IF one had to handbook…

What about export used cars? That is very green from a levelheaded waste side. And if you buy a used car that gets excellent fuel efficiency, like an ancient civic, I have to wonder if that is greener than export a new hybrid…?

My only additional thought is export cleaner burning diesel engines, like some of the new volkswagons, in view of the fact that diesel has historically better fuel efficiency, so if they find a way to hegemony their dirtier emissions (which it seems like VWs did..?) that seems like a excellent selection too.

Any additional view?

Be grateful all!