The correct answer is D because benefit groups in Workday are driven by benefit group eligibility rules, and the Benefit Group Audit is specifically used to identify workers who qualify for more than one group at the same time. When a worker appears in multiple benefit groups, the root cause is almost always overlapping or conflicting eligibility logic within those group definitions. The appropriate corrective action is to review the criteria assigned to each benefit group and determine exactly why the worker satisfies both sets of rules.

Option A is not appropriate because creating an additional broad benefit group does not resolve the overlap; it would likely add more complexity and increase the risk of duplicate eligibility. Option B focuses on plan-level eligibility, which is downstream from the benefit group assignment and does not address why the worker entered multiple groups in the first place. Option C relates to event processing and enrollment timing, not foundational eligibility setup. To ensure a worker is only eligible for one benefit group, the administrator must refine or correct the group eligibility rules so the criteria are mutually exclusive and aligned with the intended benefits population.