The best approach in this situation is for the project manager to engage directly with the experienced team member to address the behavior. This should be done in a supportive manner, aiming to understand the reasons behind the team member's actions and to find a constructive way forward. This aligns with conflict resolution strategies that emphasize problem-solving and collaboration, which are considered effective in project management and business analysis contexts. By addressing the issue privately, the project manager can prevent further team disruption and work towards a resolution that maintains team cohesion and productivity.
References: The answer is verified with the principles of conflict resolution as outlined in the PMBOK Guide and the Professional in Business Analysis (PMI-PBA) reference materials, which suggest that direct and supportive communication is key to resolving such conflicts123.