Senior management has the primary responsibility for resolving any fraud incidents found as a result of the investigation in the treasury department. While the internal audit activity may identify and report on fraud, and forensic accountants may assist in investigating it, the responsibility for addressing and resolving incidents of fraud, including implementing corrective actions and holding parties accountable, rests with senior management.
The IIA's guidance on the roles and responsibilities in fraud investigations, which places ultimate responsibility for management of fraud risks with senior management.

Corruption in the context of unethical practices typically involves wrongdoing for personal gain or to benefit another at the expense of the organization. Demanding payment from a vendor for decisions made in the vendor ' s favor is a clear example of corruption, as it involves misuse of authority for personal benefit. The other options listed deal with accounting manipulations or reimbursement fraud, which, while unethical, are not examples of corruption as defined in auditing terminology.
Association of Certified Fraud Examiners (ACFE) - Fraud Definitions and Classifications

The chief audit executive (CAE) taking on a consultative role can appropriately coordinate and facilitate risk workshops for management. This task aligns with the advisory function of internal audit, where they support and facilitate the risk management process without directly setting the risk appetite or determining risk mitigation strategies, thereby maintaining their advisory and facilitative role without assuming management responsibilities.
International Standards for the Professional Practice of Internal Auditing; guidance on internal audit's role in consulting.

Internal controls are mechanisms put in place to reduce the probability or impact of risks affecting the organization's objectives. They do not eliminate risks entirely (which would be avoidance) nor do they transfer or share the risk (as in risk sharing); rather, they mitigate risks to more acceptable levels.
Institute of Internal Auditors (IIA) - Guidance on Risk Assessment in Practice

A monitoring activity in organization-wide risk management would include validating the results of management ' s self-assessment. This activity ensures that risk management processes are effective and that self-assessments accurately reflect the risk status, aligning with the role of internal audit in providing assurance over risk management activities.
COSO framework for risk management; IIA guidance on risk management.