Which of the following statements is correct regrding the concepts of inherent risk, control risk, and detection risk?

a. Inherent risk can be reduced if a company has a reliable system of internal controls

b. An auditor may only directly control detection risk

c. Inherent risk is increased if a company has no or inadequate internal controls

d. An auditor is unable to control any of these risks directly, but must assess each to determine the resulting audit risk