External auditors have a duty to communicate in writing significant deficiencies in internal control to those charged with governance. Which of the following is unlikely to be relevant when determining whether a 'significant deficiency' exists? a. The susceptibility to loss or fraud of the related asset. b. The extent of substantive procedures performed. c. The likelihood of deficiencies leading to material misstatements in the financial statements in the future. d. The importance of controls to the financial reporting process