Developing a stakeholder engagement plan is correct because it addresses the root cause of the problem, which is the stakeholder's concerns and reservations. By developing a stakeholder engagement plan that specifically addresses these concerns, the project manager can build trust and rapport with the stakeholder and increase their chances of supporting the project. It demonstrates a commitment to engaging with and addressing the concerns of key stakeholders, which is essential for project success.
The other options are not as appropriate and do not address the core issue of this scenario.
Excluding a resistant stakeholder, especially one whose support is crucial, is not advisable as it may lead to further conflicts and challenges.
Assigning the task of managing the resistant stakeholder to a team member is incorrect because completely shifting the responsibility to a team member without addressing the stakeholder's concerns and building a positive relationship may not effectively resolve the situation.
Involving senior management should only be considered if initial efforts to engage directly with the resistant stakeholder through a stakeholder engagement plan are unsuccessful.