Hey, I previously managed to successfully complete this application which had a similar sort of question. Burges Salmon lay out the qualities they like in trainees quite well on their website, I think this is key because they are very open about emphasising different qualities than City firms perhaps would. I think this is what they mostly want you to recognise from this question. I formatted it by having a paragraph on each of these values, why I personally felt that these qualities were important for a person to have, then linking it back to my own experiences where I have demonstrated them.
I recognise that this doesn't address the 'how will this support you' aspect, I imagine that may just link to why you find them important? Or maybe it is how these qualities will aid you through your career?
Also, when I was speaking to graduate recruitment there they told me that their longer questions were only to filter out applicants who couldn't write well. I think most of the people in graduate recruitment there have since changed, and I wasn't completely sure on the likelihood of this anyway, but I thought it was interesting.