The correct answer is A. The Family Group relational view is no longer selected. In Relativity, family relationships for emails and attachments are displayed through a relational view tied to the Group Identifier field. Relativity’s documentation explains that family groups are shown in a document list when a view is configured to display those relationships, and that the Group Identifier is the field used to associate an email with its attachments. When a relational family view is active, users can see the family grouped together in the list rather than seeing only the individual records that directly meet the filter criteria.

Once the attorney adds a filter, the list may appear to “lose” attachments if the view is no longer leveraging the Family Group relational context. This is because Relativity filters act on the records in the active view, and related items such as attachments are included through family grouping behavior rather than because every attachment independently satisfies the filter. The Group Identifier field itself is generally what defines the family relationship, and if it were not populated, the issue would be broader and structural, not just something that appears after adding a filter. The Document Extension field being indexed is unrelated to whether attachments display as family members in the document list. Therefore, the most plausible and Relativity-aligned explanation is that the Family Group relational view is no longer selected , which prevents all related email attachments from continuing to display together in the filtered Hot Documents view.