The correct answer is C. You cannot use Audit to revert coding decisions on required fields back to a null state. Relativity's official Audit documentation states that certain field types, including single choice , can be reverted. However, it also explicitly states that you cannot revert a required field if doing so would return that field to a blank null value . That is exactly what this scenario describes: the field was changed from null to Responsive, and reverting would restore it to null. If the field is required, Relativity blocks that revert because required fields cannot be blank.
This means option A is incorrect because single-choice fields can be reverted in Audit. Option B is also incorrect because Relativity supports both individual and mass revert workflows depending on the situation.
Option D is not the documented reason for the failure. The controlling issue is the required-field constraint.
From an RCA perspective, this is a subtle but important administrative behavior: the Audit system can revert field changes, but only where the resulting value remains valid under Relativity's field rules. If the revert would violate a field's required setting, the system will not allow it. Therefore, the most accurate reason is that Audit cannot revert the value because the revert would place a required field back into a null state .