The VRC's (VRC-30 * VRC-40 * VRC-50)
Fleet Logistics Support Squadron
There have only been three VRC squadrons. While there have been and still are VR squadrons..
there have only been  three with the "C" designation.
The "V" - indicates fixed wing -- The "R" - indicates transport -- the "C" - indicates -- carrier onboard delivery.
Although VR-5, VR-22, VR-23, VR-25, VR-21 and VR-24 provided COD service during their existence---they were never designated a VRC.