The answer B is correct because the most important thing for an IS auditor to review when determining whether IT investments are providing value to the business is the business strategy. The business strategy is the plan or direction that guides the organization's decisions and actions to achieve its goals and objectives.
The business strategy defines the organization's vision, mission, values, competitive advantage, target market, value proposition, and key performance indicators (KPIs).
IT investments are the expenditures or costs incurred by the organization to acquire, develop, maintain, or improve its IT assets, such as hardware, software, network, data, or services. IT investments can help the organization to support its business processes, operations, functions, and capabilities. IT investments can also help the organization to create or enhance its products, services, or solutions for its customers or stakeholders.
To determine whether IT investments are providing value to the business, an IS auditor needs to review how well the IT investments align with and contribute to the business strategy. Alignment means that the IT investments are consistent and compatible with the business strategy, and that they support and enable the achievement of the strategic goals and objectives. Contribution means that the IT investments are effective and efficient in delivering the expected outcomes and benefits for the business, and that they generate a positive return on investment (ROI) or value for money.
An IS auditor can use various methods or frameworks to review the alignment and contribution of IT investments to the business strategy, such as:
* Balanced scorecard: A balanced scorecard is a tool that measures and monitors the performance of an organization across four perspectives: financial, customer, internal process, and learning and growth. A balanced scorecard can help an IS auditor to evaluate how well the IT investments support and improve each perspective of the organization's performance, and how they link to the organization's vision and strategy.
* Value chain analysis: A value chain analysis is a tool that identifies and analyzes the primary and support activities that add value to an organization's products or services. A value chain analysis can help an IS auditor to assess how well the IT investments enhance or optimize each activity of the value chain, and how they create or sustain a competitive advantage for the organization.
* Business case analysis: A business case analysis is a tool that evaluates the feasibility, viability, and desirability of a proposed project or initiative. A business case analysis can help an IS auditor to examine how well the IT investments address a business problem or opportunity, how they deliver the expected benefits and outcomes for the stakeholders, and how they compare with alternative options or solutions.
The other options are not as important as option B. Return on investment (ROI) (option A) is a metric that measures the profitability or efficiency of an investment by comparing its benefits or returns with its costs or expenses. ROI can help an IS auditor to quantify the value of IT investments for the business, but it does not capture all aspects of value, such as quality, satisfaction, or impact. ROI also depends on how well the IT investments align with the business strategy in the first place. Business cases (option C) are documents that justify and support a proposed project or initiative by describing its objectives, scope, benefits, costs, risks, and alternatives. Business cases can help an IS auditor to understand the rationale and expectations for IT investments, but they do not guarantee that the IT investments will actually deliver the desired value for the business. Business cases also need to be aligned with the business strategy to ensure their relevance and validity. Total cost of ownership (TCO) (option D) is a metric that measures the total costs incurred by an organization to acquire, operate, maintain, and dispose of an IT asset over its life cycle. TCO can help an IS auditor to estimate the financial impact of IT investments for the business, but it does not reflect the benefits or outcomes of IT investments, nor does it indicate how well the IT investments support or enable the business strategy.
References:
* IT Strategy: Aligning IT & Business Strategy
* How To Measure The Value Of Your Technology Investments
* IT Investment Management: A Framework for Assessing ... - GAO
* How To Align Your Technology Investments With Your Business Strategy

A post-implementation review (PIR) of a newly modified IT application focuses on ensuring that the system meets business and security requirements effectively. The sufficiency of implemented controls (A) is the most critical aspect because it ensures that security, operational, and compliance controls are functioning correctly.
These controls include access controls, data integrity checks, and audit logs to prevent unauthorized access, data corruption, or security breaches.
Other options:
Resource management plan (B) is important for project management but is not the primary concern for an IS auditor in a post-implementation review.
Updates required for end-user manuals (C) are necessary for usability but do not impact the security or operational integrity of the system.
Rollback plans for changes (D) are important for change management but are typically assessed before deployment, not in a PIR.
Reference: ISACA CISA Review Manual, IT Governance and Management of IT

User requirements are the foundation of any successful application. Properly defining what the application needs to do and how it should serve users is critical before moving into design or development.
References:
Project Management Methodologies (Agile, Waterfall, etc.): All major methodologies emphasize the criticality of understanding user requirements during the initial project phases.
Software Development Lifecycle (SDLC): Requirements gathering is a cornerstone of the initiation phase within the SDLC.
ISACA Resources: While not explicitly tied to a CISA document, ISACA's emphasis on governance and aligning IT with business objectives reinforces the importance of starting with clear user requirements.

Information security policies are high-level statements that define the organization's approach to protecting its information assets from threats and risks. They should be based primarily on a risk management process, which is a systematic method of identifying, analyzing, evaluating, treating, and monitoring information security risks. A risk management process can help ensure that the policies are aligned with the organization's risk appetite, business objectives, legal and regulatory requirements, and stakeholder expectations. An information security framework is a set of standards, guidelines, and best practices that provide a structure for implementing information security policies. It can support the risk management process, but it is not the primary basis for defining the policies. Past information security incidents and industry best practices can also provide valuable inputs for defining the policies, but they are not sufficient to address the organization's specific context and needs. References: Insights and Expertise, CISA Review Manual (Digital Version)

The best criteria for monitoring an IT vendor's service levels are the performance metrics, as they provide quantifiable and measurable indicators of how well the vendor is delivering the agreed-upon services, such as availability, reliability, quality, timeliness, and customer satisfaction. A service auditor's report is a document that provides an independent opinion on the vendor's controls and processes, but it may not reflect the actual service levels or performance. A surprise visit to the vendor may help to verify the vendor's compliance and operations, but it may not be feasible or effective for monitoring the service levels on a regular basis. An interview with the vendor may help to obtain feedback and insights from the vendor's perspective, but it may not be objective or reliable for monitoring the service levels. References: CISA Review Manual (Digital Version), Chapter 2: Governance and Management of IT, Section 2.4: IT Service Delivery and Support