An unusually high-performing team member has begun showing a drop in performance and aggressive behavior toward colleagues during meetings. The project manager has worked with this person for months and has not seen this behavior before. What should the project manager do?

The project manager should first discuss their observations directly with the individual. This approach respects the individual's privacy and provides an opportunity for them to explain their behavior, which could stem from personal issues, project-related stress, or other factors unknown to the project manager. This direct communication is a crucial first step in conflict resolution and performance management. Discussing with other team members (option A) is unprofessional and could lead to gossip. Attending more meetings (option B) is passive and delays addressing the issue directly. Escalating to HR and the functional manager (option D) is premature without first attempting to resolve the issue directly with the team member.