What step does the specialist being relieved take to call for extra help if necessary?

In the context of air traffic control, when a specialist recognizes that they cannot manage a situation alone and requires additional support, the appropriate response is a review. This step involves assessing the current operational status and determining the necessity for extra personnel or resources. By conducting a review, the specialist can clearly articulate the challenges they are facing and specify the level of assistance required, ensuring a more structured and effective approach to managing the situation. This context reinforces the importance of communication and operational integrity in maintaining safety within the airspace.

The other options represent different concepts or procedures that might not align with the specific protocol for calling for help. For instance, an assistance request denotes a general plea for help without the critical assessment process that a review implies. Crisis management is more about dealing with the fallout from high-stress situations rather than calling for immediate support. A help call may seem like a straightforward request for assistance but lacks the structured evaluation of the situation that is essential in the air traffic control environment.