Which forward observer control option requires FO to contact the FIST for each call for fire?

The option that indicates the forward observer (FO) must contact the Fire Support Team (FIST) for each call for fire is centralized control. In a centralized control option, the FIST is responsible for coordinating all fire support requests and ensuring that they are properly executed. This means that the FO does not directly engage with fire support assets but instead relays their requests to the FIST. The FIST then manages the prioritization and execution of those requests based on the tactical situation and available assets.

This method can often lead to better coordination and allocation of fire support resources, as the FIST has a comprehensive view of the battlefield and can make informed decisions on where and when to employ fires effectively. The communication between the FO and the FIST is critical in this model, requiring the FO to initiate contact for each request, ensuring that all actions are synchronized and efficiently managed.