Correct Answer: DThe appropriate course of action for the project manager in this situation is to work with the product owner to clarify the requirement. The product owner is responsible for defining and prioritizing the product backlog, which includes acceptance criteria for tasks. They serve as the main point of contact between the development team and the stakeholders, ensuring that the team's work aligns with the client's needs and expectations. Therefore, collaborating with the product owner is the most direct and efficient way to obtain the necessary information to clarify the task for the developer.