Which of the following statements reflects an auditor's responsibility for detecting errors and fraud?

a. An auditor is responsible for detecting employee errors and simple fraud, but not for discovering fraud involving employee collusion or management override.

b. An auditor should plan the audit to detect errors and fraud that are caused by departures from GAAP.

c. An auditor is not responsible for detecting errors and fraud unless the application of GAAS would result in such detection.

d. An auditor should design the audit to provide reasonable assurance of detecting errors and fraud that are material to the financial statements.