Final answer:
The correct form for requesting tracer action on shipments sent by insured certified mail is typically one provided by the postal or courier service, not the DoD forms listed. Forms such as the USPS Missing Mail Search request might be used for postal services specific postal or courier service used for the shipment.
Step-by-step explanation:
The form used to request tracer action on shipments sent by insured certified mail would likely be a form specific to the postal or courier service handling the shipments. The Department of Defense (DoD) forms listed in the question (DD 1348, DD 200, DD 230, DD 120) are related to military logistics, property loss, and requisitions, which may not be relevant for standard postal service operations.
When dealing with certified mail, customers typically use forms or processes provided by the postal service, such as a Missing Mail Search request through the United States Postal Service (USPS) if applicable. It is important to use the correct form for tracer actions to ensure timely and accurate responses from the postal services regarding the status of insured shipments. Anyone looking to track a shipment or file a claim for an undelivered or lost parcel through certified mail should refer to the guidelines and resources provided by the specific postal or courier service used for the shipment.