The consultant should recommend the Grants Management product which includes the Grants Portal feature. This is the packaged route that keeps the process supportable, auditable, and aligned to the data model.
The Core Concept Explained: Experience Cloud design is driven by persona, authentication, scale, and sharing. The wrong template or license can create unnecessary cost, weak security, or excessive customization.
Step-by-Step Technical Analysis: Begin with the external persona, authentication requirement, and transaction volume. Select the Experience Cloud license or template that matches that access pattern, then configure sharing sets, external OWD, site visibility, and page access. Finish by testing the experience as anonymous, authenticated, and internal users. Use Grants Management with the Grants Portal capability.
Why the Incorrect Options Are Wrong: A does not meet the implementation-quality bar for security, scale, auditability, or maintainability in this scenario. B does not meet the implementation-quality bar for security, scale, auditability, or maintainability in this scenario. D does not meet the implementation-quality bar for security, scale, auditability, or maintainability in this scenario.