Certification audits are carried out byCertification Bodies (CBs), not the organization itself. ISO/IEC 27001 requires external certification audits to be independent, impartial, and objective. According to ISO/IEC 27006 (Requirements for bodies providing audit and certification of ISMS), the Certification Body determines theaudit duration and number of audit daysbased on factors such as organizational size, complexity, scope, and risk environment. This ensures consistency across organizations and prevents manipulation by the auditee. ISO/IEC 27001 Clause 9.2 and 9.3 addressinternal audit and management review, but the determination of certification audit days is outside the organization’s control; it rests solely with the accredited Certification Body auditors. Thus,Answer: Bis correct, as the CB’s external auditor formally calculates and assigns the audit time.