By communicating the results of the impact assessment to the stakeholder, the project manager ensures that the sponsor and other stakeholders are fully aware of the implications of the requested change. This transparency is crucial for informed decision-making. Negotiating the needed resources and time with the stakeholder helps align the project's scope, schedule, and budget with the new objective. It also allows the stakeholders to understand the trade-offs and make decisions on priorities. Therefore, option A is the most comprehensive and strategic approach, ensuring that the project manager and stakeholders collaboratively address the change, assess priorities, and align resources and schedules to meet the new objective effectively.