The most useful analytical method when trying to identify groups with similar behavior or characteristics in a large population is classification. Classification is a technique that assigns data points to predefined categories or classes based on their features or attributes. Classification can help to discover patterns, trends, and relationships among the data and reveal the similarities or differences among the groups. Classification can also help to support decision making, prediction, or recommendation based on the data analysis. References:
* CISA ReviewManual (Digital Version), Chapter 3, Section 3.4.21
* CISA Online Review Course, Domain 2, Module 3, Lesson 12

The most assurance over the completeness and accuracy of loan application processing with respect to the implementation of a new system can be obtained by running historical transactions through the new system.
Historical transactions are transactions that have been processed and recorded by the old system in the past.
Running historical transactions through the new system can provide the most assurance over the completeness and accuracy of loan application processing, bycomparing the results and outputs of the new system with those of the old system, and verifying whether they match or differ. This can help identify and resolve any errors or issues that may arise from the new system, such as data conversion, functionality, compatibility, etc.
Comparing code between old and new systems is a possible way to obtain some assurance over the completeness and accuracy of loan application processing with respect to the implementation of a new system, but it is not the most effective one. Code is a set of instructions or commands that define how a system operates or functions. Comparing code between old and new systems can provide some assurance over the completeness and accuracy of loan application processing, by checking whether the logic, algorithms, or functions of the new system are consistent or equivalent with those of the old system. However, this may not be sufficient or reliable, as code may not reflect the actual performance or outcomes of the system, and may not detect any errors or issues that may occur at the data or user level. Reviewing quality assurance (QA) procedures is a possible way to obtain some assurance over the completeness and accuracy of loan application processing with respect to the implementation of a new system, but it is not the most effective one. QA procedures are steps or activities that ensure that a system meets its quality standards and requirements, such as testing, verification, validation, etc. Reviewing QA procedures can provide some assurance over the completeness and accuracy of loan application processing, by evaluating whether the new system has been properly tested and verified before implementation. However, this may not be adequate or accurate, as QA procedures may not cover all aspects or scenarios of loan application processing, and may not reveal any errors or issues that may arise after implementation. Loading balance and transaction data to the new system is a possible way to obtain some assurance over the completeness and accuracy of loan application processing with respect to the implementation of a new system, but it is not the most effective one. Balance and transaction data are data that reflect the status and history of loan applications in a system, such as amounts, dates, payments, etc. Loading balance and transaction data to the new system can provide some assurance over the completeness and accuracy of loan application processing, by transferring data from the old system to the new system and ensuring that they are consistent and correct. However, this may not be enough or valid, as balance and transaction data may not represent all aspects or features of loan application processing, and may not indicate any errors or issues that may arise

The most effective control to maintain segregation of duties in a DevOps environment is A. Enforce approval prior to deployment by a member of the team who has not taken part in the development. Segregation of duties (SoD) is a principle that requires multiple actors to complete a task to reduce the risk of fraud, error, or abuse1. In a DevOps environment, where developers and operators work together to deliver software faster and more reliably, SoD may seem to be incompatible or impractical. However, SoD can still be achieved by implementing controls that ensure that no single person can develop, test, and deploy code without oversight or review2.
Enforcing approval prior to deployment by a member of the team who has not taken part in the development is an effective control that ensures that code changes are verified and validated by a peer before they are released to production. This control can help prevent or detect any unauthorized or malicious modifications, errors, or vulnerabilities in the code, and ensure that the code meets the quality and security standards3. This control can also promote collaboration and feedback among the team members, and improve the transparency and accountability of the software delivery process3.

The IS auditor's primary focus when evaluating an organization's offsite storage facility should be the adequacy of physical and environmental controls. Physical and environmental controls are essential to protect the offsite storage facility from unauthorized access, theft, fire, water damage, pests or other hazards that could compromise the integrity and availability of backup media. Shared facilities is something that the IS auditor should consider when evaluating the offsite storage facility, but it is not the primary focus. Results of business continuity plan (BCP) test or retention policy and period are things that the IS auditor should review when evaluating the organization's BCP or backup strategy, not the offsite storage facility itself. References: ISACA, CISA Review Manual, 27th Edition, 2018, page 388