The correct choice is the one that will still work after release. The best answer is A. Create a custom-based sharing rule.; B. Update the organization-wide defaults. The scenario is asking for platform configuration, and the reason is straightforward: 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 wording points to this control because the business result must be reliable when real users work with real records.
For the stated requirement - Ursa Major Solar (UNS) uses a public sharing model for accounts. UNS would like to move to a more restrictive sharing model but wants the Sales team to continue to have access to all account records with the sales. - the selected answer handles the behavior directly. It is not just a way to make the page look cleaner or to remind users what to do. It places the responsibility in the Salesforce feature that owns the outcome. That matters in an App Builder implementation because access, automation, relationships, page rendering, reporting, and deployment each have different enforcement points.
The distractors are not equal substitutes. C (Update the Sales profile.) should be rejected because it works at the wrong scope for the object, field, page, automation, or deployment condition in the stem. D (Create an owner-based sharing rule.) would be fragile here because Sharing controls record visibility; it does not change field type, page composition, or automation timing. That is the kind of solution a Salesforce admin can document, migrate, and troubleshoot without creating hidden technical debt.
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