A Scrum team is refining product backlog items for the next sprint in a project.

The product owner is responsible for managing the product backlog and ensuring that it reflects the priorities and vision of the product. While the Scrum team can suggest changes or improvements during the refinement process, the product owner has the final say on what changes are made to the backlog. This ensures that the product backlog aligns with business needs, stakeholder expectations, and the overall product vision. Therefore, the product owner can reject changes to the backlog if they believe the changes do not align with these priorities.