During my last job interview which I did end up getting the job, when I was asked this question I answered honestly. I told them I’m not the best, fastest, or smartest, and I was young in my trade craft, but I twisted it to a positive, in that I followed up with that made me eager for learning new skills and makes me more of a blank slate to train.
When I told them I’m not the best, fastest, or smartest, I also mentioned that I was never told I lacked effort and drive and that I never shy away from learning opportunities.