Which of the following actions by the internal audit activity requires disclosure to the board...

Nonconformance with the Standards that requires disclosure to the board includes the failure to conduct external assessments within the timeframe stipulated by the IIA standards. Specifically, Standard 1312 requires that an external quality assessment must be conducted at least once every five years. Not completing this assessment within the last seven years constitutes a nonconformance that must be reported.

Institute of Internal Auditors (IIA) Standards, specifically Standard 1312 on External Assessments.