The Bottom Line (Direct Answer): answer: C, D, E - C (Add the Decision Explainer Log History component to..); D (Integrate the BRE with Decision Explainer.); E (Assign the Decision Explainer Permissions Set License..). This maps the scenario to the Salesforce-native capability that owns the requirement.
The Core Concept Explained: Business Rules Engine externalizes decision logic from custom code.
Expression Sets orchestrate calculations and can call decision assets so policy thresholds remain maintainable by authorized business users.
Step-by-Step Technical Analysis: Identify the inputs that drive the decision, declare them as Expression Set resources, and use Decision Matrices or Decision Tables where business users must maintain rule thresholds.
Execute representative samples before activation, then confirm the output and Decision Explainer history match the expected eligibility, fee, or prioritization result. Integrate BRE with Decision Explainer, add the Decision Explainer Log History component to the relevant Lightning record pages, and assign the Decision Explainer permission set license to the appropriate users.
Why the Incorrect Options Are Wrong: A can orchestrate work, but it is not the preferred rule-decision asset for maintainable fee, eligibility, or prioritization logic. B adds a custom build path and increases lifecycle, security, and upgrade effort when a packaged or declarative capability already supports the requirement.

Disable the Grant Access Using Hierarchies setting on the Case object. This maps the scenario to the Salesforce-native capability that owns the requirement.
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. Disable Grant Access Using Hierarchies on the Case object where supported for the Employee Experience security design.
Why the Incorrect Options Are Wrong: A points to a disablement approach that either is not supported for the tested feature or would remove a capability the scenario depends on. 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.

The internal users are missing the Emergency Response Management permission set. This selection keeps the implementation declarative and within the intended Public Sector operating model.
The Core Concept Explained: Licensing and permitting configuration depends on packaged regulatory objects and relationships. Using those objects preserves compliance history, fee logic, inspections, and renewals in a consistent model.
Step-by-Step Technical Analysis: Trace the licensing or permitting path from applicant intake to regulatory authorization, fee calculation, inspection, approval, and renewal. Configure the packaged LPI objects and dependencies before adding automation so that reporting, compliance history, and Experience Cloud application flows remain aligned. Assign the Emergency Response Management permission set to the affected internal users.
Why the Incorrect Options Are Wrong: A may look related, but it does not place the logic in the correct declarative Public Sector or OmniStudio configuration layer. C may look related, but it does not place the logic in the correct declarative Public Sector or OmniStudio configuration layer. D may look related, but it does not place the logic in the correct declarative Public Sector or OmniStudio configuration layer.

Action Plans. This answer fits because the requirement is about the specific platform mechanism named in the option, not a nearby workaround.
The Core Concept Explained: Action Plans standardize repeatable work. They package tasks, dependencies, due dates, and document checklist requirements so staff do not rely on memory or one-off manual steps.
Step-by-Step Technical Analysis: Start by defining the target object that owns the operational work. Build or select the Action Plan Template, add the required tasks or Document Checklist Items, publish the template, and then automate or guide its association to the live record. Test that owners, due dates, dependencies, and applicant-facing upload prompts behave correctly. Use Action Plans to create repeatable inspection task sets from templates.
Why the Incorrect Options Are Wrong: A may look related, but it does not place the logic in the correct declarative Public Sector or OmniStudio configuration layer. C may look related, but it does not place the logic in the correct declarative Public Sector or OmniStudio configuration layer. D may look related, but it does not place the logic in the correct declarative Public Sector or OmniStudio configuration layer.

Create or modify a sharing set for the Profile used for the Site that gives access to Cases. This is the lowest- customization answer that still satisfies the business, security, and lifecycle requirements.
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. Create or modify a sharing set for the Experience Cloud user profile.
Why the Incorrect Options Are Wrong: B shifts the process onto Case even though the scenario is centered on application, license, permit, grant, or inspection records. C shifts the process onto Case even though the scenario is centered on application, license, permit, grant, or inspection records. D shifts the process onto Case even though the scenario is centered on application, license, permit, grant, or inspection records.