Which of the following indicates that internal audit independence may be compromised?

A: The internal auditor maintains a close personal relationship with operational management. B: Material observations were intentionally left out of the audit report. C: Internal auditors assigned to the audit engagement did not have the knowledge, skills, and competencies needed to perform their responsibilities. D: An internal auditor failed to apply professional skepticism while performing audit tests in an area overseen by an experienced, reputable manager