Factor which activates prekallikrein -: (A) Factor VIII, (B) Factor II, (C) Factor X, (D) Factor XII
Answer is D. Ans. is 'd' i.e., Factor XIIo Initiation of intrinsic coagulation pathway occurs when factor XII is exposed to negatively charged surfaceo This leads to activation of factor XII to XIIa.o Factor XIIa can then hydrolyze prekallikrein to kallikrein, which in turn activates more XII to XIIa.