Sounds strange, but... what trim level is my Prius??

I know this sounds strange, and I feel silly asking, but was filling out my profile on here, and I have no idea what my trim level my Prius is. I know that they come in I through V. I bought it used from a Honda dealership. It was a lease that was traded in. The trim level wasn't listed anywhere and I don't know how to tell.

It's a 2008. No leather, no sunroof, single CD player, has a backup camera, but from what I see, does NOT have a navigation system.

If there is a link to find the info, that would be great. A great professor of mine always said "It's not a stupid question if you don't know the answer!"

Thanks!