The Act phase of the PDCA cycle is where the organisation takes actions to improve its processes and performance based on the results of the Check phase. This may involve resetting objectives to make them more realistic, achievable or challenging, or implementing changes to address the root causes of problems and achieve the desired outcomes. The Act phase is also where the organisation monitors the effects of the actions taken and evaluates their effectiveness and efficiency. The Act phase is important because it enables the organisation to learn from its experience and continually improve its ISMS. References: What is 'Plan, Do, Check, Act'? A framework for continuous improvement, PDCA in ISO27001 - Free guide to learn | Dr. Erdal Ozkaya, PECB Candidate Handbook ISO 27001 Lead Auditor (page 12)

Explanation
The following are purposes of information security, except increasing business assets. Increasing business assets is not a purpose of information security, as it is not directly related to protecting information and systems from threats and risks. Information security may contribute to increasing business assets by enhancing customer trust, reputation, compliance, and efficiency, but it is not its primary goal. Ensuring business continuity is a purpose of information security, as it aims to prevent or minimize disruptions or losses caused by incidents affecting information and systems. Minimizing business risk is a purpose of information security, as it aims to identify and reduce threats and vulnerabilities that may compromise information and systems.
Maximizing return on investment is a purpose of information security, as it aims to optimize the costs and benefits of implementing and maintaining information security controls and measures. References: : CQI & IRCA ISO 27001:2022 Lead Auditor Course Handbook, page 23. : [ISO/IEC 27001 Brochures | PECB], page
4.

The mail sent by the CEO giving his views on the status of the company and the company's future strategy and the CEO's vision and the employee's part in it should be classified as internal mail. Internal mail is a type of classification that indicates that the information is intended for internal use only, and should not be disclosed to external parties without authorization. The mail sent by the CEO contains information that is relevant and important for the employees of the company, but may not be suitable for public disclosure, as it may contain sensitive or confidential information about the company's performance, goals, or plans. Reference: : CQI & IRCA ISO 27001:2022 Lead Auditor Course Handbook, page 34. : CQI & IRCA ISO 27001:2022 Lead Auditor Course Handbook, page 37. : [ISO/IEC 27001 LEAD AUDITOR - PECB], page 14.

Explanation
Knowledge is the understanding of facts, concepts, principles, theories and practices related to a specific subject or discipline. Skills are the ability to apply knowledge and use know-how to complete tasks and solve problems. According to ISO 19011:2018, the knowledge and skills of an auditor include the following:
* Knowledge of audit principles, procedures and methods
* Knowledge of management system standards and reference documents
* Knowledge of the organization's context, scope, processes and objectives
* Knowledge of relevant legal, regulatory and contractual requirements
* Knowledge of applicable industry, sector or technical disciplines
* Knowledge of risk management and risk-based thinking
* Skill in collecting and verifying information
* Skill in evaluating conformity and effectiveness of management systems
* Skill in reporting and communicating audit results
* Skill in managing audit activities and teams
Based on this, the activities that are predominately related to knowledge are designing a checklist and determining what evidence to gather, as they require the auditor to understand the audit criteria, scope, objectives and methods, as well as the organization's context, processes and risks. The other activities are more related to skills, as they involve applying knowledge and using know-how to perform tasks and solve problems during the audit.
References:
* ISO 19011:2018, Guidelines for auditing management systems, clauses 7.2.1, 7.2.2 and 7.2.3
* PECB Candidate Handbook - ISO 27001 Lead Auditor, pages 9-10 and 16-17
* ISO 9001 Auditing Practices Group Guidance on: Auditing Competence, pages 2-3 and 8

The two phrases that would apply to 'check' in the Plan-Do-Check-Act cycle for a business process are:
C. Verifying training
F. Auditing processes
C. This phrase applies to 'check' in the PDCA cycle because it involves measuring and evaluating the effectiveness of the training activities that were implemented in the 'do' phase. Training is an important aspect of information security awareness, education, and competence, which are required by clause 7.2 of ISO 27001:20221. Verifying training can help the organisation to assess whether the staff have acquired the necessary knowledge, skills, and behaviour to perform their roles and responsibilities in relation to information security. Verifying training can also help the organisation to identify any gaps or weaknesses in the training program and to plan for improvement actions.
F. This phrase applies to 'check' in the PDCA cycle because it involves examining and reviewing the performance and conformity of the processes that were implemented in the 'do' phase. Auditing is a systematic, independent, and documented process for obtaining objective evidence and evaluating it to determine the extent to which the audit criteria are fulfilled2. Auditing processes can help the organisation to verify whether the information security objectives and requirements are met, whether the information security controls are effective and efficient, and whether the information security risks are adequately managed. Auditing processes can also help the organisation to identify any nonconformities or opportunities for improvement and to plan for corrective or preventive actions.
References:
1: ISO/IEC 27001:2022 - Information technology - Security techniques - Information security management systems - Requirements, clause 7.2 2: ISO 19011:2018 - Guidelines for auditing management systems, clause 3.2