Following injury to a blood vessel, immediate haemostasis is achieved by-
Fibrin deposition
Vasoconstriction
Platelet adhesion
Thrombosis
Robbins basic pathology, 9th edition, page no:79 Vascular injury primarily causes a transient aeriolar vasoconstriction through reflex neurogenic mechanisms augmented by local secretion of endothelin. All other options follow this. So the answer is option 2.
General pathology