The verified answer is A. Applications is the detail object in a master-detail relationship, so its record access is inherited from the Internship master. Salesforce explicitly states that custom objects on the detail side cannot have independent sharing rules, manual sharing, or queues because they do not have an independent Owner field. To let recruiters edit Application records, the app builder must therefore grant the required Read/Write access to the related Internship master records, such as through a sharing rule. Option C is invalid because the detail object ' s sharing model cannot simply be independently configured as Public Read/Write. Option D is also invalid because a detail custom object cannot have its own sharing rule in this configuration. This corrects the PDF answer key, which identifies D.

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