【单选题】

In your project, you invest a lot of time in team development to increase the team's performance, which increases the likelihood of meeting project objectives. Which of the following indicators would you use to evaluate your team's effectiveness
A．Improvement in skills of team member

B．Improvement in competencies and sentiments that help the team perform better as a grou
C．Decrease in staff-attrition( fewer people leaving the project te
D．All the abov