In extremely time-sensitive situations, ____________ may be the only message provided.

The term that fits in the context of extremely time-sensitive situations is the EXORD, which stands for Execution Order. An EXORD is a directive issued to execute a plan or operation, and it is paramount in scenarios where immediate action is required. It spells out the specific actions that need to be taken and is often used when there is minimal time for extensive pre-execution communication or coordination.

In urgent situations, other types of messages such as an alert order, fragmentary order, or operation order may not suffice due to their nature or the time required to prepare and disseminate them. An alert order typically serves to inform forces of a pending operation but does not provide detailed execution instructions. A fragmentary order, while useful for amending existing plans or enhancing clarity, may not provide the immediate and definitive instructions necessary in critical moments. An operation order is comprehensive and outlines the entire plan, but may not be quick enough to issue in a time-sensitive scenario.

Thus, the EXORD is specifically designed for immediate execution, making it the appropriate choice for situations where time is of the essence.