Final answer:
The three mechanisms that prevent or control blood loss are vascular spasms, platelet plug formation, and coagulation, not inflammation which is involved in the immune response.
Step-by-step explanation:
The combined three mechanisms that work to prevent or control blood loss include vascular spasms, the formation of platelet plugs, and coagulation resulting in the formation of stable fibrin blood clots. However, inflammation is not one of these mechanisms. Vascular spasms constrict blood flow, platelet plugs temporarily seal ruptured vessels, and coagulation involves the synthesis of fibrin which helps in forming a stable clot. Inflammation, on the other hand, serves a different role primarily associated with the body's immune response and healing but does not directly prevent or control blood loss.