Which of the following statements about internal audit's follow-up process is true?

The nature, timing, and extent of follow-up for assurance engagements is standardized to ensure quality performance.

The actions of external auditors and other external assurance providers is not encompassed by internal audit's follow-up process.

Internal auditors have responsibility for determining if management and the board have implemented the recommended action or otherwise accepted the risk.

The follow-up process must be complete and documented in the working papers in order to conclude the engagement.