Final answer:
An auditor is most likely to issue an adverse opinion when financial statements significantly deviate from GAAP, for example, when not conforming to FASB statements on loss contingencies.
Step-by-step explanation:
An auditor would most likely express an adverse opinion if the financial statements are not in conformity with generally accepted accounting principles (GAAP). Specifically, this would be the case if there are issues such as those with the FASB statement on loss contingencies, where financial statements do not appropriately account for or disclose material losses that could potentially occur and thus do not accurately represent the company's financial position. Among the options given, failing to conform to important financial reporting standards, like those concerning loss contingencies, is a direct and material misstatement that typically leads to an adverse opinion.
In the other scenarios provided, if the CEO refuses to allow access to minutes from the board of director meetings, or there are doubts about the company's ability to continue as a going concern, or if there are deficiencies in internal control, the auditor may rather give a qualified opinion, a disclaimer of opinion, or highlight the issues in the audit report without necessarily issuing an adverse opinion, depending on other audit evidence and the materiality of the issues. An adverse opinion is issued when the financial statements are, as a whole, not presented fairly in conformity with GAAP.