Validating that assets are protected according to assigned classification is the primary role of the IS auditor in an organization's information classification process. An IS auditor should evaluate whether the information security controls are adequate and effective in safeguarding the information assets based on their classification levels. The other options are not the primary role of the IS auditor, but rather the responsibilities of the information owners, custodians, or security managers. References:
* CISA Review Manual (Digital Version), Chapter 6, Section 6.2.31
* CISA Review Questions, Answers & Explanations Database, Question ID 206

The auditor should verify whether a right-to-audit clause exists (B) next, because it is a contractual provision that grants the auditor the right to access and examine the records, systems, and processes of the SaaS provider. A right-to-audit clause is important for ensuring transparency, accountability, and compliance of the SaaS provider with the customer's requirements and expectations. A right-to-audit clause can also help the auditor to identify and mitigate any risks or issues related to the SaaS agreement12.
Verifying whether IT management monitors the effectiveness of the environment (A) is not the next step, because it is a part of the ongoing monitoring andevaluation process, not the initial walk-through procedures.
The auditor should first establish the scope, objectives, and criteria of the audit before assessing the performance and controls of the SaaS provider.
Verifying whether a third-party security attestation exists © is not the next step, because it is not a mandatory requirement for a SaaS agreement. A third-party security attestation is a report or certificate issued by an independent auditor that evaluates and validates the security controls and practices of the SaaS provider. A third-party security attestation can provide assurance and confidence to the customer, but it does not replace or eliminate the need for a right-to-audit clause3.
Verifying whether service level agreements (SLAs) are defined and monitored (D) is not the next step, because it is not directly related to the audit process. SLAs are contractual agreements that specify the quality, availability, and performance standards of the SaaS provider. SLAs are important for measuring and managing the service delivery and customer satisfaction, but they do not grant or guarantee the right to audit4.

The best method to determine if IT resource spending is aligned with planned project spending is earned value analysis (EVA). EVA is a technique that compares the actual cost, schedule, and scope of a project with the planned or budgeted values. EVA can help to measure the project progress and performance, and identify any variances or deviations from the baseline plan1.
EVA uses three basic values to calculate the project status: planned value (PV), earned value (EV), and actual cost (AC). PV is the amount of work that was expected to be completed by a certain date, according to the project plan. EV is the amount of work that was actually completed by that date, measured in terms of the budgeted cost. AC is the amount of money that was actually spent to complete the work by that date1.
By comparing these values, EVA can determine if the project is on track, ahead, or behind schedule and budget. EVA can also calculate various indicators, such as cost variance (CV), schedule variance (SV), cost performance index (CPI), and schedule performance index (SPI), to quantify the magnitude and direction of the variances. EVA can also forecast the future performance and completion of the project, based on the current trends and assumptions1.
The other options are not as effective as EVA in determining if IT resource spending is aligned with planned project spending. Option B, return on investment (ROI) analysis, is a technique that evaluates the profitability or efficiency of an investment, by comparing the benefits or revenues with the costs. ROI analysis can help to justify or prioritize a project, but it does not measure the actual progress or performance of the project against the plan2. Option C, Gantt chart, is a tool that displays the tasks, durations, dependencies, and milestones of a project in a graphical format. Gantt chart can help to plan and monitor a project schedule, but it does not show the actual cost or scope of the project3. Option D, critical path analysis, is a technique that identifies the longest sequence of tasks or activities that must be completed on time for the project to finish on schedule. Critical path analysis can help to optimize and control a project schedule, but it does not account for the actual cost or scope of the project4.
References:
* Earned Value Analysis & Management (EVA/EVM) - Definition & Formulae1
* Return on Investment (ROI) Formula2
* What Is a Gantt Chart?3
* Critical Path Method for Project Management