The correct answer is C, Consolidated billing. This feature in AWS Organizations allows you to consolidate billing and payment for multiple AWS accounts under a single paying account. This provides a centralized view of costs across all your accounts, enabling you to track and report the combined charges more efficiently. Service control policies (SCPs) are used to manage permissions and controls within an organization, Cost Explorer is a tool for visualizing and managing AWS costs and usage, and AWS Identity and Access Management (IAM) is for managing access to AWS services. These options do not provide the consolidated billing functionality.