At the end of the first sprint, a project lead notices one team member is underperforming. Which type of communication should the lead use to address the issue?

Informal verbal communication, such as a private conversation, is the most appropriate initial approach. It allows for a direct, empathetic, and confidential discussion about performance concerns, fostering trust and providing an opportunity to understand the root cause without immediately escalating the situation. Formal verbal communication (like a retrospective discussion) would be too public and potentially embarrassing for the individual. Formal written communication (like an email copied to a manager) is overly aggressive for a first step and could damage morale and trust. Informal written communication (a friendly reminder) lacks the personal touch needed to address performance issues effectively.