Which of the following ratings of Sailors is assigned to work center 74C?

The correct rating assigned to work center 74C is Aviation Electronics Technician (AT). This rating specializes in the maintenance, troubleshooting, and repair of electronic systems and equipment installed on naval aircraft. Work center 74C, being a part of aviation maintenance, primarily focuses on the electronic components of aircraft, making the AT rating the most relevant in this context.

While the other ratings have distinct roles within the Navy, they do not align with the primary functions of work center 74C. Hospital Corpsman (HM) focuses on medical and health services, Boatswain's Mate (BM) deals with seamanship, navigation, and various tasks related to deck operations, and Intelligence Specialist (IS) works with intelligence and information analysis. Therefore, the AT rating is the appropriate choice for work center 74C due to its specific alignment with aviation electronics responsibilities.