Answer: b. Shawna has her formal gown dry-cleaned so that it will be ready for her to wear at the event
Step-by-step explanation:
The behavior that's related to dress or posture that will be most effective in helping Shawna accomplish her goals is that Shawna has her formal gown dry-cleaned so that it will be ready for her to wear at the event.
Unlike other options such as her clasping her hands behind her back so that the audience cannot see them shaking, and to project confidence and her crossing her arms to appear powerful and in charge, having her dress ready for the event is appropriate as it will help achieve her goal
Therefore, the correct option is B.