AW Computing tracks order information in custom objects called order__c and order_Line_ c - Currently, all shipping information is stored in the order__c object. The company wants to expand Its…

A master-detail field only on `Order_Line__c` would link the shipment group to the order lines but wouldn't directly associate the shipment group with the parent `Order__c`, making it harder to manage shipments for a complete order.

A master-detail field only on `Order__c` would link the shipment group to the entire order, but wouldn't allow for specific `Order_Line__c` records to be assigned to different shipment groups within that order.

A new `Order_shipment_Group__c` object is necessary to represent a distinct shipment group. This new object needs a master-detail relationship to `Order__c` to link it to the parent order and another master-detail relationship to `Order_Line__c` to associate specific order lines with that particular shipment group, thereby allowing multiple lines from one order to be assigned to different shipment groups.

A master-detail field on `Order_shipment_Group__c` pointing to itself would create a self-referencing relationship, which is not suitable for linking shipment groups to orders and order lines.