I'm sure the system is set up with a lot of questions, in case you don't remember some. You probably have to just get a certain number of them correct. (You seriously don't remember the color of your first car?? I remember the color of all of my cars!)
So, they'd probably ask the color of a different car or the style/make or whatever - something you don't currently own. Or what your job was in a certain year. What schools you went to, what city someone was married in, year they were married, etc. A lot of these things kids would have no clue, but could be verified with the right software.
Any licensed private investigator has access to the DMV, but the average person can't even buy access, so it's not so bad.
Yes the system has the ability to skip questions if you just can't remember but it does replace those questions with similarly personal questions.
Yes its pulled from everything from DMV to credit systems of basic info you would be surprised just how much information is out there about each and every one of us lol.