The personal quality of integrity is most likely the foundation for the relationship where senior management relies on the professional judgment of an internal auditor. Integrity ensures that the auditor conducts her work ethically and objectively, provides truthful and accurate assessments, and adheres to both the standards of the profession and the organization's policies. This quality builds trust and reliability in the auditor's findings and recommendations.
The IIA's Code of Ethics and International Standards for the Professional Practice of Internal Auditing.

Control activities are specific actions defined by management aimed at mitigating risk to the achievement of objectives. They are part of the broader internal control framework, which management designs according to the organization's risk management strategies. These activities can vary widely across different organizations depending on the specific risks they face and the strategies management employs to mitigate these risks.
COSO Framework on Internal Controls

According to IIA guidance, any additional roles beyond traditional audit functions, such as being responsible for risk management and investigation, must be explicitly defined in the internal audit charter. This document, approved by senior management and the board, delineates the scope and responsibilities of the internal audit function, ensuring clarity and proper governance. Thus, if the internal audit charter stipulates such roles, it justifies the CEO's decision.
IIA Standard 1000 - Purpose, Authority, and Responsibility

Organizing volunteers from the organization to provide periodic plantation skill sharing to farmers represents a corporate social responsibility (CSR) activity. This initiative not only supports community development but also aligns with sustainable agricultural practices, which is especially relevant for an agricultural organization.
This activity focuses on giving back to the community and enhancing sustainability, both key aspects of CSR.
Definitions and examples of CSR in industry guidelines

Consulting engagements often involve providing advice or opinions at management's request. In this case, providing input on the accounting pronouncements falls under a consulting capacity, consistent with IIA definitions of consulting services.