Which of the following sources of performance data typically provides the most reliable performance judgments?

A) the employee herself
B) the employee's peers or team members
C) the employee's subordinates
D) the employee's supervisor
E) the employee's customers

The employee's supervisor typically provides the most reliable performance judgments as they are responsible for overseeing the employee's work and have a higher level of authority and access to information about the employee's performance compared to other sources. Additionally, the supervisor is usually more experienced and knowledgeable in evaluating employee performance and providing feedback.