For me it depends how you define smart. I always think being smart isn't just being able to learn things, but to have the awareness to apply it to something useful.
For example:
For a while I was a member of Mensa. I was enrolled in their gifted and talented program while I was at school. The more I learned about it as I grew up and the more people I met who were part of it made me realise it wasn't for me so I left.
I dropped out of university to chase a girl I met playing in bands and stuff. I'm now married to her with two kids, a wonderful life and all that good stuff. Not the actions of a smart man, but it worked out in the end.
Work as a web developer, so not dumb, but nothing too fancy.
So for me, whenever I answer this question, I always say that I'm not smart (what idiot drops out of university to chase a girl) but I have a propensity for learning.
Also I'm from the UK and our education system is a little different. I'm not 100% sure what the UK equivalent is for each of the options in the poll.
I'd say the equivalent would probably be some college if your highest formal education was uni before dropping out to chase a girl.
Yeah one thing I've learned since graduating high school, being a college student now, is that you cannot define intelligence by what degree someone holds. I realize in high school, smart kids have high GPAs and dumbasses have low ones, but that's not how the world in general works.
I am majoring in physics and to my friends in poly science, I seem smart because I can do some advanced mathematics, but that doesnt mean I am smarter than them, however no matter how hard I try, i cannot understand economics, while they claim to be able to. Maybe if I took an economics course, I'd get it but who knows.
I think I disagree with your definition of smart. Being able to learn something is what makes you smart. Having the knowledge obtained from learning. At the risk of sounding like wanna be enlightened philosopher, I'll say I think that applying that smartness is wisdom/experience.
Also smart people make stupid choices. I didnt drop out to chase a girl, but I skipped several days of classes to drive 500 miles to see my boyfriend and now I'm spending valentines day alone.