Using tags in Azure allows you to assign custom key-value pairs to resources, enabling you to categorize and track costs based on project, department, environment, or any other relevant classification for your organization. The correct answer results in granular tracking of costs, which aids in precise cost attribution per project or department. The incorrect answers either represent tools that are not primarily used for cost attribution (like Azure Advisor primarily for recommendations on practices), do not offer the level of detail required for this specific task (like a single Azure subscription without further classification), or exceed the scope of the question (like implementing full IaC practices, which might help with resource deployment but not directly with cost attribution).