The correct answer is D) a round-table discussion.
The strategy that would be best to help you determine the pros and cons about a proposed dress code policy is a round-table discussion.
One of the most common methods to discuss something in an open and respectful way is a round table discussion. A round-table is a form of exchanging ideas in order to reach a solution of something. Participants accord a specific topic, talk and debate. The members of the round-table have discuss in equity and there is no sense of authority to undermine any point of view.
That is why a round table would be best to help determine the pros and cons about a proposed dress code policy, and after that, make a decision once every member of the round-table had made his/her point.