Think of a situation where there was maybe a lot of things going on maybe involving different priorities.
Did you identify there was a situation involving a high priority?
Did you take ownership of it rather than pass it on to another person/section?
Did you say you would get something done within a set time frame and stick to it?
Did you need to involve others to get the right outcome?
Did you check to make sure they understood why it was a high priority?
Did you make sure the promised outcome was met and in time?
Have you identified points in a process that could be improved upon? What was it and How did you improve It?
You need to show how you went above and beyond what a lot of folk would have done in the same situation.
Imagine someone on benefit 'phones up and says a something is wrong and it turns out it WAS.
Some may say they'll change it and e-mail the appropriate section and the person would need to wait for a few days for it to be actioned and payment to be received.
Some may change it, 'phone the section manager, tell them they will receive an e-mail confirming the change, say why it is urgent, ask if the payment can be released the same day, ask when it will be received and then let the claimant know.
It helps if the example is job-related but it needn't be, mind.