Which of the following is the most effective way for internal auditors to determine whether...

To effectively determine whether ethical values are followed throughout an organization, internal auditors should review employee survey responses and follow up on those that suggest weaknesses in the ethical climate. This approach allows auditors to gather firsthand insights from employees about the actual ethical environment, which can be more telling than formal documentation or compliance with written policies alone. It provides a direct measure of the ethical culture as experienced and perceived by the employees themselves.

Institute of Internal Auditors (IIA) - International Standards for the Professional Practice of Internal Auditing; Guidance on assessing organizational culture.