A project manager is in the middle of the executing process when a stakeholder suggests a major new change. This change will cause the third major overhaul of the project. At the same time, the project manager discovers that a major work package was not completed because a team member's boss moved him to another project that had a higher priority. Which of the following is the BEST person for the Project Manager to address these issues with?

A: The team

B: Senior Management

C: Customer

D: The sponsor