According to the PMBOK® Guide, specifically within the Monitor Stakeholder Engagement process, projects characterized by a high degree of change (such as those using agile or adaptive methodologies) require continuous and proactive management of stakeholder relationships.

Dynamic Engagement: In high-change environments, stakeholder needs, influence, and interest levels can shift rapidly. The project manager must use the Stakeholder Engagement Plan as a living document, constantly monitoring the effectiveness of engagement strategies and adjusting them as the project evolves.

Continuous Feedback Loops: Rather than relying on static communication, the project manager monitors relationships to ensure that stakeholders remain aligned with project goals. This involves using data analysis (such as stakeholder engagement assessment matrices) to identify gaps between desired and actual engagement levels.

Adaptive Strategies: The " Monitor " process ensures that if an engagement strategy is no longer working due to a change in project direction or stakeholder turnover, the project manager can implement a corrective action to bring stakeholders back into the fold.

Analysis of Other Options:

B. Send all project documents to stakeholders each time they are modified: This is an example of information overload. Sending every technical or minor update to all stakeholders can lead to " noise, " causing them to ignore critical communications and decreasing their overall engagement.

C. Schedule monthly meetings with the stakeholders, including team members: In a project with a high degree of change, monthly meetings are likely too infrequent. High-change projects typically require more frequent interaction (such as bi-weekly reviews or daily stand-ups in agile) to ensure stakeholders stay informed.

D. Engage only with the project sponsors: While sponsors are critical, the definition of a stakeholder includes anyone who can affect or be affected by the project. Ignoring other stakeholders (users, customers, functional managers) leads to missed requirements and potential resistance later in the project.