What is the first step in determining if a unique passenger is eligible to fly?

The first step in determining if a unique passenger is eligible to fly is to establish theater eligibility. This process involves verifying that the individual meets specific criteria based on military or operational requirements, especially for those traveling in a military context. In many cases, the eligibility to fly can depend on factors such as deployment status, military affiliation, and authorization for travel to certain destinations.

The other options, while relevant in different contexts, do not serve as the initial determination of eligibility to fly. Assessing health status is important for ensuring that passengers are fit for travel, but this usually follows the establishment of basic eligibility criteria. Reviewing travel history can provide insights into past flights and adherence to travel policies, but this is more of a secondary consideration. Checking baggage is a process that occurs much later and is not related to determining flight eligibility. Therefore, establishing theater eligibility is the correct and logical first step in this process.