Choice "A" is correct. An internal auditor must refrain from assessing specific operations for which they were responsible within the previous year. Objectivity is presumed to be impaired if an internal auditor provides assurance services for an activity for which the internal auditor had responsibility within the previous year.
Choice "c" is incorrect. An internal auditor must refrain from assessing specific operations for which they were previously responsible but may be involved in consulting activities for specific operations for which they were previously responsible.
Choice "b" is incorrect. An internal auditor must refrain from assessing specific operations for which they were previously responsible but may be involved in consulting activities for specific operations for which they were previously responsible.
Choice "d" is incorrect. An internal auditor must refrain from assessing specific operations for which they were previously responsible but may be involved in consulting activities for specific operations for which they were previously responsible.