An approval process is the correct architecture because the requirement combines conditional approval routing with an auditable approval history. Salesforce approval processes define the criteria under which a record enters approval, specify the approval steps, identify the appropriate approvers, and preserve the state of the approval request.

The consultant can use the application's age or duration as the entry or step criterion and route qualifying records to the appropriate manager. Salesforce's approval framework tracks states such as Submitted, Pending, Approved, Rejected, Reassigned, and Recalled. The Approval History related list provides users with visibility into the record's progress and creates the audit trail required by the scenario.

A Flow that merely changes ownership doesn't constitute manager approval and doesn't inherently provide the same approval-process audit model. Chatter is a collaboration mechanism rather than a controlled regulatory approval system. An "approval escalation rule" isn't the correct Salesforce automation construct for this requirement.

Salesforce now recommends Flow Approval Processes as the modern successor for many new implementations, providing dynamic routing and detailed compliance logging; however, among the supplied answer choices, C precisely describes the required approval-process pattern.

Study Guide Reference: Agentforce Public Sector Implementation Strategies and Best Practices – application approvals; approval criteria; manager routing; Approval History; regulatory auditability.