The Governance domain underscores the importance of understanding root causes before implementing corrective actions. Investigating why project managers failed to conduct proper stakeholder assessments (Option A) allows the PMO professional to identify systemic issues such as unclear processes, lack of training, or other barriers.

Sending reminders or providing training (Options B and D) are appropriate but should follow the investigation to target solutions effectively. Reviewing project manager selection (Option C) is relevant but secondary and may not address process or knowledge gaps.

PMI standards stress the value of diagnosis and root cause analysis as the first step in governance-related corrective actions.