The key is to separate behavior from appearance. The best answer is C. Configure Campaign Hierarchies and Campaign stasmics. The Platform App Builder role is to choose the standard Salesforce capability that owns the behavior: data structure, access, automation, user experience, reporting, or deployment.
The selected answer is stronger because it meets both the functional requirement and the maintainability requirement. In a Salesforce implementation, a solution that only works for one user, one page, or one data sample is not good enough. The correct feature has to behave consistently across the intended profiles, record types, apps, and devices that are part of the design.
None of the other options gives the same administrative control. A (On an opportunities pipeline report) does not fit cleanly; Reporting configuration helps analysis, but it does not enforce the requested record behavior.
B (Online Account Hierarchies and Raft Up Summary fields) is only a partial match because it does not provide the same direct administrative control as the selected option. D (Change to a public security model) is not enough: it would require extra assumptions that the scenario does not support. This is the stronger design because it respects security, data quality, user experience, and lifecycle management at the same time.
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