The best description of an audit risk is that the financial report may contain undetected material errors. Audit risk is the risk that the auditor expresses an inappropriate opinion on the financial report when it contains material misstatements or errors. Audit risk consists of three components: inherentrisk, control risk, and detection risk. Inherent risk is the susceptibility of an assertion or a control to a material misstatement or error due to factors such as complexity, volatility, fraud, or human error. Control risk is the risk that a material misstatement or error will not be prevented or detected by the internal controls. Detection risk is the risk that the auditor's procedures will not detect a material misstatement or error that exists in an assertion or a control. References:
* CISA Review Manual (Digital Version)
* CISA Questions, Answers & Explanations Database

The most effective way for the audit team to leverage the risk management maturity of the organization is to integrate the risk register for audit planning purposes. The risk register is a document that records the identified risks, their likelihood, impact, and mitigation strategies for a project or an organization. By using the risk register, the audit team can align their audit objectives, scope, and procedures with the organization's risk profile and priorities. This will help the audit team to provide more value-added and relevant assurance and recommendations to the management and stakeholders.
Some of the web sources that support this answer are:
* Audit Maturity And Risk Management | Ideagen
* Building a Mature Enterprise Risk Management Plan | AuditBoard
* CISA CertifiedInformation Systems Auditor - Question0551

The best way to provide assurance of the integrity of a firewall log is to ensure that the log cannot be modified. A firewall log is a record of the traffic and events that occur at the firewall, which is a device or software that controls and filters the incoming and outgoing network traffic based on predefined rules and policies. The integrity of a firewall log means that the log is accurate, complete, consistent, and valid, and that it has not been altered, deleted, or corrupted by unauthorized or malicious parties. The IS auditor should verify that the firewall log has adequate controls to prevent or detect any modification of the log, such as encryption, hashing, digital signatures, write-once media, or tamper-evident seals. The other options are not as effective as ensuring that the log cannot be modified, because they either do not address the integrity of the log data, or they are monitoring or retention measures rather than preventive or detective controls. References: CISA Review Manual (Digital Version)1, Chapter 5, Section 5.2.4