Which of the following is a joint service multi-mission aircraft with VTOL capabilities?

The V-22 Osprey is a joint service aircraft that is designed for multiple missions and possesses vertical takeoff and landing (VTOL) capabilities. This unique capability allows it to operate from smaller spaces and in environments where traditional fixed-wing aircraft cannot. The Osprey combines the advantages of a helicopter's vertical flight with the speed and range of a turboprop airplane, enabling it to perform various missions including troop transport, logistics support, and medical evacuation.

In contrast, the other aircraft listed do not have VTOL capabilities or are not designed for multi-mission roles in the same way as the Osprey. The C-2A Greyhound is primarily used for carrier onboard delivery and does not have VTOL capabilities. The MH-53E Sea Dragon is a heavy-lift helicopter designed for mine countermeasures and has some versatility but is not classified as a multi-mission aircraft with VTOL. The S-3B Viking is primarily a carrier-based anti-submarine warfare aircraft and also does not possess the VTOL capability that defines the Osprey.