If it just says "write a bubblesort", chances are I would, without asking any questions.
If you write the bubble sort without asking questions and without suggesting a better way of sorting, you would not be the ideal employee I'm looking for. There are employers who want their people to do whatever they say, without asking questions. I think a question like this is a good way to find out if employer and possible employee match.
The wording would be "Write a bubble sort". Of course, somewhere much earlier in the interview, you'd have to mention that you're not looking for typing monkeys :)
It's a trick question for a reason. It's a test. If you explicitly state you want suggestions, it is no longer a test.