Final answer:
Internal audit performs self-assessments to determine the effectiveness of its own controls.
Step-by-step explanation:
The correct answer is a. Internal audit.
Internal audit plays a crucial role in an organization by reviewing and evaluating the effectiveness of its own controls. This process involves examining the internal processes and controls established by the organization to ensure they are efficient and aligned with the company's objectives. Self-assessments help identify areas that need improvement and suggest changes to enhance controls. Through this approach, internal audits can contribute significantly to the overall success of the organization by ensuring that the controls in place are effective and efficient.