It seems you've been preparing for this for a little while. I bet you know a lot more than you think!
I didn't get any questions like that in the exam, though I was expecting at least one. I doubt the diagram would include the name of the design pattern e.g Iterator. However, it would probably include Aggregate. The point is, there are only 23 patterns to choose from and they are all quite obvious from the UML diagrams. If you're worried, focus on the patterns with slightly similar diagrams. They're not out to trick you. You'll either know the pattern or you won't.