Which option signifies that there’s a request to prioritize an ongoing task?

The option that signifies a request to prioritize an ongoing task is "Expedite current assignment." This phrase clearly indicates that there is a need to accelerate the progress of the task at hand. In dispatch operations, the term "expedite" is often used to communicate urgency, suggesting that resources or attention should be redirected to the ongoing assignment to ensure it is completed more quickly than initially planned.

By using the word "current," it emphasizes that this is not just about starting a new task but about placing importance on what is already in progress. This request typically arises when circumstances change, necessitating that certain tasks receive priority over others to meet time-sensitive requirements or respond to urgent situations effectively.

The other options do not convey the same level of urgency regarding a current task. For example, "Assignment complete" indicates that a task has already been finished, while "Check for wanted" relates to a different procedure, and "Disregard last transmission" instructs to ignore previous communications, which does not imply prioritization of ongoing work.