Which of the following statements is true concerning the concept of performance materiality? a. performance materiality is set less than overall materiality and the auditor determine the extent of audit evidence. b. if performance materiality is set too low, the auditor might not perform sufficient procedures to detect material misstatements in the financial statements. c. if performance materiality is set too high, the auditor might perform more substantive procedures than necessary. d. performance materiality is essentially the same posting materiality. e. all of the above are true.