The correct answer is A because the symptom is specifically about Case ownership not changing after a Medical Inquiry is submitted. Salesforce Help for Medical Inquiries shows that the inquiry workflow uses Case status values such as Draft, Signed, Submitted, and Assigned, and Life Sciences Cloud also provides Trigger Handler Administration for configuring Life Sciences trigger handlers, including trigger handlers related to Case objects.
In the scenario, the status update is working correctly: the signed inquiry becomes Submitted. That means the submission process itself is functioning. The failure is isolated to ownership routing: the Case remains owned by the field sales rep instead of being routed to the Medical Science Liaison team or queue. Based on the available options, CaseChangeOwnershipHandler is the handler that directly corresponds to changing ownership on the Case record.
Option B, MSLInquirySubmissionHandler, sounds related to Medical Inquiry submission, but the submission status already updates correctly, so that is unlikely to be the inactive piece. Option C, CaseMSLQueueHandler, sounds like queue routing, but the Salesforce-style handler name that most directly describes the failed behavior is CaseChangeOwnershipHandler. Since the issue is ownership transfer after submission, the inactive trigger handler is CaseChangeOwnershipHandler.
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