Final answer:
Performance evaluation is not part of engagement performance in a CPA firm's system of quality control but refers to individual employee assessments.
Step-by-step explanation:
In the context of a CPA firm's system of quality control, the element of engagement performance refers to how an audit is planned, executed, and supervised. Quality control should include procedures for performance evaluation, engagement performance itself, and supervision and review responsibilities. Among the options provided, Performance evaluation is ordinarily not considered part of engagement performance within a CPA firm's system of quality control. Instead, performance evaluation is more typically associated with individual employee assessments in an organizational context, such as reviews conducted by a manager to assess an employee's work performance and develop future work plans. Therefore, choice A, Performance evaluation, does not fit within the element of engagement performance for a CPA's quality control system.