Final answer:
On 23 May 1978, the CNO enhanced roles for chief petty officers, who hold critical positions in the Navy. Their responsibilities include duties as quality assurance officers and technical experts. The specified roles in the question don't encompass the chief petty officers' roles as defined on that date.
Step-by-step explanation:
On 23 May 1978, the CNO (Chief of Naval Operations) approved new roles and responsibilities for chief petty officers within the United States Navy. The roles and responsibilities of chief petty officers are critical in maintaining the efficiency and operational effectiveness of the Navy.
While specific roles like combat specialist, aircraft mechanic, supply officer, and navigator are crucial to naval operations, chief petty officers were not only designated to these roles. Aside from their technical and tactical expertise, they serve primarily as technical experts, quality assurance officers, and supervisors within their respective naval commands.
It is important to highlight that the designated role among the options given is not directly stated in public domain sources for the specified date. Therefore, providing answer options like combat specialist, aircraft mechanic, supply officer, or navigator might not fully capture the breadth of their responsibilities designated on that particular date without additional context.