The effectiveness of a control monitoring program can be measured by how quickly it can detect and correct any control failures that may compromise the achievement of the organization's objectives. A shorter time between control failure and failure detection means that the control monitoring program is able to identify and report the issues promptly, and initiate the remediation actions accordingly. This can reduce the impact and likelihood of the risks associated with the control failures, and enhance the performance and reliability of the controls. The other options are not as good indicators of the effectiveness of a control monitoring program, because they do not reflect the timeliness and responsiveness of the program, but rather the scope, effort, or frequency of the program. References = Risk and Information Systems Control Study Manual, Chapter 4, Section 4.3.3, page 130.

Segmenting the application within the existing network is the most effective control to manage a legacy application that relies on software that has reached the end of extended support, as it isolates the application from the rest of the network and reduces the attack surface and the potential impact of a compromise.
Subscribing to threat intelligence, applying patches for a newer version of the application, and increasing the frequency of regular system and data backups are not the most effective controls, as they may not address the root cause of the risk, or may introduce additional costs or complexities, respectively. References = CRISC Review Manual, 7th Edition, page 153.

Updating a risk register with assessment results for a key project must primarily capture action plans to address risk scenarios requiring treatment.
* Risk Register Purpose:
* Documentation of Risks: The risk register is a central repository for all identified risks and their respective treatment plans. It ensures that all risks are documented, tracked, and managed throughout the project lifecycle.
* Action Plans: It is crucial to document action plans for risks that require treatment. This ensures that there are clear strategies in place to mitigate or manage these risks.
* Importance of Action Plans:
* Mitigation and Management: Action plans detail the steps necessary to mitigate identified risks, providing a clear path for risk management. This is vital for ensuring that risks do not negatively impact the project.
* Accountability and Tracking: Including action plans in the risk register assigns responsibility and timelines for risk treatment, which is essential for accountability and tracking progress.
* References:
* According to ISACA's guidelines, a comprehensive risk register should include action plans for addressing risk scenarios. This ensures that all identified risks are managed effectively and that appropriate actions are taken in a timely manner.

The MOST critical requirement to include in the contract is the confidentiality of customer data, because it is a legal and ethical obligation of the bank to protect the privacy and security of its customers' personal and financial information. Outsourcing the statement printing function to an external service provider exposes the customer data to potential unauthorized access, disclosure, or misuse by the service provider or its sub-contractors. Therefore, the contract should specify the terms and conditions for the handling, storage, and disposal of the customer data, as well as the penalties for any breach of confidentiality. The other options are not as critical as the confidentiality of customer data, because:
* Option A: Monitoring of service costs is an important requirement to ensure that the service provider delivers the statement printing function within the agreed budget and scope, but it is not as critical as the confidentiality of customer data, which has legal and reputational implications for the bank.
* Option B: Provision of internal audit reports is a useful requirement to verify that the service provider complies with the internal and external standards and regulations for the statement printing function, but it is not as critical as the confidentiality of customer data, which is a core value of the bank and its customers.
* Option C: Notification of sub-contracting arrangements is a relevant requirement to ensure that the service provider does not delegate the statement printing function to another party without the bank's consent and oversight, but it is not as critical as the confidentiality of customer data, which is the primary responsibility of the bank and its service provider. References = Risk and Information Systems Control Study Manual, 7th Edition, ISACA, 2020, p. 197.