Final answer:
The auditor investigates control exceptions to understand their cause and impact.
Step-by-step explanation:
The auditor always needs to investigate any control exceptions (deviations) that he or she identifies during testing to find out, to the extent practical, the cause and impact of the deviations.
By investigating control exceptions, the auditor can identify the underlying issues or weaknesses in the organization's internal controls that led to the deviations. This helps the auditor understand the risks and potential impacts on the financial statements. The investigation may involve conducting interviews, reviewing documentation, and performing additional procedures to gather sufficient evidence.
Ultimately, the goal of investigating control exceptions is to provide assurance that the organization's internal controls are functioning effectively and to make appropriate recommendations for improvements or corrective actions if necessary.