Which of the following can be used to help you or other project managers on future projects?

A sponsor is a stakeholder role and a person, not an artifact or reference tool that can be consulted on future projects.

A project charter authorizes a specific project and is unique to that engagement; it does not serve as transferable guidance for unrelated future projects.

A stakeholder is a person or group affected by the project, not a document or repository of reusable knowledge.

Project documentation, especially lessons learned registers and historical project records, preserves decisions, outcomes, and best practices from the current project in a form that future project managers can reference and apply. This is the primary vehicle for transferring organizational knowledge across projects over time.